Adult education is a little different to being at school, college or university but there are certain unavoidable similarities.
e.g. Can you reasonably expect to be good at painting if you do not paint?
Will your French Cuisine improve if you do not cook at home?
Do you expect to speak fluent Spanish when you do not practice daily?
Adults have far less time to commit to education.
There are many intruding responsibilities and concerns; work, family, health etc.
However, learning is learning; you get out of it only what you put into it.
There is no miracle method/secret formula unique to adults; if anything you may need to try a little harder than you did as a child.