What does Galatians 5:13 tell believers to do instead of using their liberty for the flesh?

Les teaches that Christian liberty is a grace-based freedom, illustrated by the fact that no one is mandated how much they give; some may give 30, 40, or 50 percent, while others give considerably less. He warns that this liberty must not become an occasion to the flesh, as if being saved means doing whatever one wants. True believers know better, while those with only a pseudo salvation or emotional experience might take that approach. Returning to Galatians 5:13, Les quotes: use not liberty or our freedom for an occasion to the flesh, but by love serve, or be literally a bond slave for one another. He notes Paul writes to Galatian believers in various congregations, so the instruction is primarily for believers among themselves, believers with believers, to be like servants through love one to another. He also references his definition of biblical love, or agape love, from John's Gospel where Jesus asked Peter, Peter, lovest thou me.