Don't worry. One of the best things about destination weddings are that they can be as easy or as hard as you'd like. Some people just show up and let the resort take care of everything, others plan every little detail themselves. It's completely up to you!
Personally, I started out saying I was just going to let the resort do the work. Next thing you know, I made my own invitations, my own decorations, I hired my own photographer, and I designed all the little details. I just had a lot of extra time and since I wasn't planning on doing them, if I had time and I was bored, I figured that was one extra little touch. Definitely nothing to get stressed out about!
Good luck!