Couple of different methods that I have used for making or adding rivets. A small drop of white glue has worked for me in the past, if it's too large, I just wipe it off and start again. Also a product called Grandt Line makes assorted sized rivets that can be glued in place.
The best CA glue IMO is Zap-A-Gap. But I have used Flash when unable to get any Zap.
Medium consistency seems to be the most effective though occasionally I will use thin.
Happy Modelling and God Bless
Robert