If you decide to get some action photos of yourself whether is in the water or on the slopes or skatepark you have to first bare in mind that what you will capture and have as a finished piece may not necessarily be a beautiful trick with a clean landing... with this in mind no need to worry too much about the "make it happen" but more about the commitment, the height, the grabs, the spray, the light, the angle, etc... all those little details which can make a basic move into something seriously cool on camera.
That said you have to set up your mind first and have an action plan before going for the photoshoot... time is precious and you don't want to have a cameraman annoyed with you as you don't really know what to do or where to go. So...
What tricks do I want and what kind of shot do I want of them close up? Do I want some spray in it? do I want my face on the photo? do I want to have the brand i promote visible? Think about all of this and then discuss it with the photographer before action.
Am I going to stay at the same spot during the all photoshoot or shall with split the time in half to find another location?
Discuss this with the cameraman and ask him/her advice on the answer... most of the time they know exactly what they want and you just have to understand what they have in mind too.
If you are shooting for a brand, a sponsor or whatever, you might want to take the opportunity of the photoshoot to actually shoot as much products as you can...
All you want is to keep your dignity because if you are riding in a bikini you certainly don't want to have the lens straight between your legs, so think of it before getting too excited about your amazing grab and don't forget to keep your legs closed :)
If you can manage to get few shots before you fall in the water it is nice. With the motion of dry hair you can have some really cool results... most of the time better to let your hair loose. Same thing with the wet hair... play with it, check your head, leave some hair in front of your eyes, hair in motion while you jump is always sick.
Adding some accessories sometimes can be fun. It can be sunnies, hat, drinks, ... think about a proper "mise en scene" and try to think about original angles
Try to have bright colors on you... it is always much easier to edit when the photographer have light and good exposure... and the contrasts are always nice.
Better to go on sunny day but never forget about those fabulous golden hours... early morning or sunset are the most precious hour for photos.
Also a cloudy sky can look amazing but it still needs to have to have enough light.
It is always better to go slow and talk with the cameraman instead of jumping around not knowing what you are doing and the results. Ask him/her... is it good like this? Am I well placed? Am I too close, too far? Be efficient and if one of your tricks has been captured then move on to the next one... no need to have 100 times the same photo.