How to go
For the Galapagos Islands, I would recommend a tour. A few medium-sized ships tour the islands with daily tender trips in to one of the islands. These tend to be 2 hour visits for wildlife adventures, then return to the mother ship. The islands do not have bathroom facilities, so long visits are not a great idea.
Most tours will require flight to Quito, Ecuador. You will meet tour personnel there and take a short flight to the island with a landing strip (left from World War two). You will board the main ship for your tour of the various islands that make up the Galapagos.
Going on your own is not a good idea. Ship/boat traffic is carefully controlled by Ecuador to maintain the natural conditions in this region. The number of ships are very limited.
What you will see and experience
Camera equipment is best contained in freezer-strength plastic bags in a back-pack or tote bag.
But...WOW, check out these photos: