It is simalar to teaching a dog. When I was younger I had more time & my rats knew many tricks, now they only know a few. Tricks I have tought some of my rats to do: sit pretty, come, shake, give kisses, lay down, crawl, walk on hind legs, push a ball, jump up & roll over. Short training sessions, lots of patience and lots of praise. It is easier to teach tricks to rat when the trick comes naturally. Like the rats that love to lick is easier to teach kiss and some like to stand on the back legs which makes walking & sit pretty easier to teach. Also most females are more active and easier to teach active tricks to as they want to have something to do. Most males are just lap rats and love to cuddle. In the past my rats cages were always left open and I was lucky as 95% of the time my rats just went back in the cage to potty, now that I close the cages when I am not there some do potty out of the cage but not a lot, luckily it is easy to clean.