What a wonderful question! As is written in the Moral Law, as Jesus had done, and as His disciples with Paul had continued to do!

Remember the sabbath day, to keep it holy. Six days shalt thou labour, and do all thy work: But the seventh day is the sabbath of the Lord thy God: in it thou shalt not do any work, thou, nor thy son, nor thy daughter, thy manservant, nor thy maidservant, nor thy cattle, nor thy stranger that is within thy gates: For in six days the Lord made heaven and earth, the sea, and all that in them is, and rested the seventh day: wherefore the Lord blessed the sabbath day, and hallowed it. Exodus 20:8-11

While six days are for work,

They say unto him, Caesar's. Then saith he unto them, Render therefore unto Caesar the things which are Caesar's; and unto God the things that are God's. Matthew 22:21

which has become part of rendering unto Caesar what is due unto Caesar (taxes and civil obedience and such), the seventh day is for rest, or in other words rendering unto God what is asked of by God (love and moral obedience).

For the Son of man is Lord even of the sabbath day. Matthew 12:8

Resting and keeping the Sabbath is a recognition of Jesus as the Creator and the Redeemer of all things. To rest is to rest from any works that seek to earn wages, whether physical in the form of money or spiritual in the form of salvation. So what does this type of rest entail? Does it mean that you trap yourself in between four walls and read the paint of the ceiling all day? Absolutely not!

Do you want to drive down to the beach? Go for it! But rather than make it a day to swim and tan and please yourself, walk alongside the beach and marvel at the ebbing and flowing of the waves. Witness the waters washing away the impurities of the sea, and think about how the blood of the Lamb washes away the impurities of the soul. See how the sands have been set as the boundaries of the waters, just as God has promised (Jeremiah 5:22), and discover the love of God in His creation.

At that time Jesus went on the sabbath day through the corn; and his disciples were an hungred, and began to pluck the ears of corn and to eat. Matthew 12:1

Do you want to go out and have a picnic in the park with your friends? Go for it! The Sabbath is a day to smile, to be joyful and glad, to laugh and delight in learning more and more of the relationship which God wants to have with you.

And now when the even was come, because it was the preparation, that is, the day before the sabbath, Mark 15:42

But just as a picnic is prepared the day before, prepare the food on the day of preparation, the Friday, in order to have the focus of the day be on the relationship between you, your friends, and God. Share testimonies with each other in how you have witnessed the love of God in your life and throughout your week.

And he said unto them, What man shall there be among you, that shall have one sheep, and if it fall into a pit on the sabbath day, will he not lay hold on it, and lift it out? How much then is a man better than a sheep? Wherefore it is lawful to do well on the sabbath days. Matthew 12:11-12

Do you see or know someone who has gotten into terrible trouble on the Sabbath day? Perhaps they are abandoned on the side of the road with no one to help them for miles. Go and help them! But do so with a smile on your face and the love of God in your heart because that someone may be heart-sick. In those moments when you are helping him when no one else would, share with him the love of Jesus who verily loves him even if no one else did.

Then said Jesus unto them, I will ask you one thing; Is it lawful on the sabbath days to do good, or to do evil? to save life, or to destroy it? And looking round about upon them all, he said unto the man, Stretch forth thy hand. And he did so: and his hand was restored whole as the other. Luke 6:9-10

If someone is sick and in desperate need for care, bring them health! Care for them as Jesus had done on the Sabbath for the man possessed (Mark 1:21-26), for the mother-in-law of Simon (Mark 1:29-33), for the man with the withered hand (Mark 3:1-5), for the woman with 18 years of illness (Luke 13:10-17), for the man with the severe and often fatal condition of dropsy (Luke 14:1-6), for the man 38 years alone and suffering because of the traditions of the Pharisees (John 5:2-9), and for the man born blind (John 9). The Sabbath is all about restoring health and relationship.

And he came to Nazareth, where he had been brought up: and, as his custom was, he went into the synagogue on the sabbath day, and stood up for to read. And Paul, as his manner was, went in unto them, and three sabbath days reasoned with them out of the scriptures, Luke 4:16, Acts 17:2

Some could have a spiritual sickness caused by mixing the ceremonies and traditions of the Pharisees with the Moral Law of God, so bring them, just as Jesus had done on the Sabbath day, and just as Paul had done on the Sabbath day after learning of the example of Jesus, the truth which is found in Jesus (John 14:6) as written in His Word (Matthew 4:4). If you are the one who is spiritually sick, then go and listen to the preaching of the Word for the healing of the sick (Matthew 9:35).

Not forsaking the assembling of ourselves together, as the manner of some is; but exhorting one another: and so much the more, as ye see the day approaching. And the next sabbath day came almost the whole city together to hear the word of God. Hebrews 10:25, Acts 13:44

Come together in relationship with your brothers and sisters in Christ, exhort one another and uplift one another in the name of Jesus Christ. Go together and listen to the Word being preached on the Sabbath day. Take advantage of the rest which God has provided in His Sabbath in order to hear His Word and learn of the relationship that He wants to have with you. Grow in faith and hope, but most importantly grow in love.

For the Son of man is Lord even of the sabbath day. Matthew 12:8

The entirety of the Ten Commandments, the Moral Law which is the fulfillment of the ceremonial law and has absolutely nothing to do with the laws of tradition, is given as a joy and a delight for the healing of the sick and the sanctification of the soul. There are no set rules or regulations as tradition may dictate, but there is the command to rest from the works that seek to earn wages, and begin to develop the very character of God whose transcript He has written in His Moral Law.

The Sabbath day is the day, the "yom" in the original language which represents a literal evening-morning 24 hour day, that God has specifically ordained and given as a gift in order to grow in a loving relationship with Him. It is the sign which He has given as a recognition of His morality being the only moral authority in your life. The day does matter, because God said. And the way to keep it is also as God said, as a day of joy and delight in the love and for the glory of God.

For this is the love of God, that we keep his commandments: and his commandments are not grievous. 1 John 5:3

And if you are struggling with harsh and exacting rules that people have taught as being Biblical and a part of the Moral Law that was written directly by God, then know that none of those grievous rules are in harmony with the Bible. Go back to the Bible and study what Jesus and the disciples did together, as a family, on the Sabbath day! The Moral Law, especially the Sabbath, will never be grievous or burdensome.

By this we know that we love the children of God, when we love God, and keep his commandments. 1 John 5:2

For the Sabbath is the signature of God that represents the character of God, not as a stern task-master as represented by scribes and Pharisees, but as a character which prefers others over self, and which prefers Jesus and His love, as shown through obedience to His Ten Commandments, above all.

If ye love me, keep my commandments. By this we know that we love the children of God, when we love God, and keep his commandments. John 14:15, 1 John 5:2

Because obedience to the Moral Law is not a work of salvation, it is a work of a loving faith that finds its completion in rest.

Come unto me, all ye that labour and are heavy laden, and I will give you rest. Matthew 11:28