They do blood/urine tests, eye sight, audigrams, you'll have to accomplish a few exercises to prove your joints/body is up to the minimal standard of the Navy-this includes the duck walk; all of this is done in underwear and a small hospital type gown. You'll have to have your girl bits checked out to make sure you're a girl like you say, and that you don't have any...other problems. You'll also have to account for your physical health all the way back to birth, any major scarring needs to be explained, and history of major illness/ailments/surgeries etc. If you have tattoos they'll want to know what they are and where. Basically they check from head to toe, every nook and cranny. It's a long day and it will give you the first real look at 'hurry up and wait' and being treated like a boot.

After you're approved you stand in a bunch of lines, sign a bunch of papers, go where they tell you to and eventually you choose a rate. You may go in wanting one specific rate, but it's not always offered to you right away. If you want to hold out and stay in DEP longer and you can get your rate you want then go for it, but don't pick a rate because the Navy has romanticized it on a sheet of paper.