Please read the passage before reading the commentary.
Paul has been reasoning with the Galatians. Some were wanting to accept circumcision and the works of the law. Paul objected that they had already accepted the Spirit and learned how to live according to the Spirit. Living according to the law negates the work of Christ. Living according to the law means living according to the flesh and its sign is circumcision, a mark on the flesh. Living according to the Spirit, on the other hand, has the reception of the Spirit as its sign.
Paul, then, lists the works of the flesh. These are all the things that break down community, things that have laws that forbid them. There are laws against sexual misbehavior, against violent actions, against drunkenness, against external manifestations of envy, anger and hatred.
Paul then lists the works of the Spirit and notes that there are no laws against them. The Spirit does not need laws, flesh does need laws. The Spirit is not tied down to specific locations. In the spirit one can be in many places at the same time, but flesh is confined to specific locations and times. Spirit has no restraint, flesh is confined by law. Spirit builds community, flesh tears it down.
Those who belong to Christ have crucified their flesh and hung it out to dry. Those who belong to Christ have clean clothing to wear.
Paul concludes the body of his letter by encouraging his Galatians Christians to continue living in the Spirit. He gives the same admonition to us: live in the Spirit and follow the Spirit.