Well, there are tons of fun things that you can do.
For lighter things, I enjoy handcuffing partners behind their backs, putting a blindfold on them sometimes, and having them give me head. You can also handcuff a partner and use something to tease their body with, give them little kisses and licks all over their body.
I am assuming that you do not want what I usually do with cuffs, as you seem to be new to them.