I'm no expert, but I've learnt a lot just by experimenting with manual settings...if you get a chance, take lots of photos of the same subjects but with different settings...try to keep a log of the settings you've used so you get a feel for what subtle and obvious differences can be achieved by playing with say, F settings etc. It takes time to learn all the combinations, and can spoil the immediacy of photography for some until or even if ever it becomes second nature to instinctively select the 'ideal' setting.
The various auto functions are really quite good, so don't beat yourself up too much when using them as default. I'd recommend a tripod for your trip, some are actually quite compact when folded...or maybe consider a monopod / camera stick...these are a great compromise between the hassle / bulk of carrying around and the steadiness required for some special pictures you have the time to set up with deliberate care.