Massage is usually done on bare skin, and this guy may just be looking for an excuse to take his clothes off with you and to have your hands on him.
Youtube has tens of thousands of videos on massage, an overwhelming number. Narrow your search. You might try "couples class massage" to find massage techniques intended for amateurs to use on each other. You probably don't have a massage table at home, and barefoot floor massage probably is the best method for you - use some combination of those terms in a Youtube search.
A few generalities that will help you give a pleasing massage: If you use your hands instead of the barefoot approach, use your whole hand, not fingertips. A little lotion or body oil will help you get appropriate glide (unless you go the barefoot route - then your fella is fully clothed and you use no lubricant). Slow, broad, deep strokes feel better than shalllow brisk strokes.
I really recommend the barefoot floor massage for you. You can apply enough pressure to do some good because your legs are stronger than your arms, and the guy doesn't have an excuse to start undressing.