If you are taking your dslr to the beach, you should plan to protect it from sea water and sea spray.
I went to Wal Mart and bought a roll of vanilla scented (bonus!) small garbage bags, like for bathrooms or the like.
Make a hole in one corner of the bottom of the bag. about 2" (4-5 cm) around.
Push your lens (lens cap on, hood off), through this opening.
Use gaffer tape to seal the bag to either your lens hood and/or the end of the lens.
I use Op/Tech straps that have quick release clips. I take the neck piece off and push the camera ends of the strap through the top of the bag, thus extending the bag falloff area to behind the top of the camera, so gravity keeps it in place. Tape around these holes to seal them and your done.
With this, you have the body and lens encased in plastic, except for the back, but you need access to the controls and LCD, so you don't want that covered anyway. The bag is long enough to hang over your hands, so the back of the camera isn't going to get too wet.
I've used this setup in rain, at the beach, on boats, etc. What you want to watch out for more than anything is salt water. Salt water kills cameras.