I was able to go to a needle exchange clinic and get a huge supply of free needles, wipes, band-aids, and they even gave me a safe disposal carton for used needles, which was awesome. Actually doing the shot isn't too much different from being anywhere else as long as you have a way to wash/sanitize your hands before, but all the supplies are just bulky to carry around. I haven't been traveling lately but when I've been away from home it was just a couple weeks so I could just bring as much supplies as I needed. Depending on how long you're traveling and how you're getting around, all the stuff might take up more space than you'd want.
Not sure what your pharmacy is like, but I've been able to switch my pickup location when I call in my refill, in case you're traveling away from your usual pharmacy. And I guess it just depends on your dose / prescription for how often you have to go back for a refill because of it being a controlled substance and all. Dealing with new pharmacies usually means a little more work on my part to mediate and get all the right info from my provider to the pharmacy, and deal with anything like that, so it's doable I think! I've only done it in NY though, so not sure if it would be harder going to other states.
Androgel might be good, but I've never tried it because I thought the idea of it getting on my clothes would make it kinda inconvenient. But I think there are patches too? I haven't tried those either, but might be worth checking out?
Good luck, hope this helps!