for larger muscle mass, do fewer reps per set(6-8) at higher weights with longer rest intervals between sets. at one end of the spectrum, fewer reps at higher weight means bigger muscles and more power, while at the other end of the spectrum, more reps at lower weight means leaner muscles and more stamina.
it sounds like you may have a universal machine in the hotel gym. that should mean you can do these exercises hopefully: bench press, military press, lat pull, upright row, leg press. this is a good starting point.
for chest do the bench press(lying on back pushing weight up away from you like a push-up)
for shoulders do the military press(sitting upright pushing weight from shoulders to above head)
for back do the lat pulldown(sitting upright pulling weight from above head down to shoulders)
also for back do upright row(sitting on ground pull weight from in front of you up to shoulders)
for triceps do pushdowns(standing upright, starting with pull-down bar in front of you arms bent at 90 degrees, keep upper arms still and push bar down so that arms are no longer bent)
for biceps do curls w/row bar(standing upright with arms down holding upright row bar bring bar up to chest by bending arms at elbow and keeping upper arms still)
for legs do leg press(sitting in the chair thing push foot pads away from body)
for abs you can do any number of ab exercises that i'm sure google will inform you about.
do cardio to keep the fat off but note that you'll need more protein and calories to gain muscle and maintain energy level, which means more food, so don't be surprised if you don't get cut.
hope this helps and good luck. also try to email fausto1 about getting onto the workout thread.