Wild rabbits are a welcome source of nutrition if you can catch or shoot one. However, rabbits are quick and aren't the easiest animal to trap or shoot. Don't be discouraged. This just means you will have to do a little work for your rabbit and working smart is always better than working hard.
Bagging your rabbits by hunting is pretty straightforward. See rabbit. Shoot rabbit. When doing this only as the chance encounter presents itself it's fine and should always be welcomed. But let's get into the specifics of how to shoot rabbits more frequently. To do this, you must go to them. That means stomping around in their homes. And their homes are not places people often like to trek. Rabbit habitats are thick areas. Remember the brer rabbit story?
Anyway, to kill rabbits you have to go where they live. Don't waste your time hunting them if they are not present. Your energy is too valuable to chance such a thing. Rabbits leave behind signs if they are present in decent numbers. Tracks and rabbit poop should be present in significant amounts before you commit to tromping through their thickets in the hopes of flushing one out and dispatching it with a well placed shot from a shotgun. Rabbit poop, commonly called rabbit pellets are small round balls roughly a quarter of an inch in diameter. Usually brown. Not as dark or quite as large as deer poop and rabbits often leave their pellets on top of stumps and logs.
It is not surprising that I am not a fan of this method of hunting where you stomp around through briar thickets trying to flush a rabbit out and hope to be able to make an accurate killing shot on it. It is in my opinion, more of a sport than an activity for survival unless you have a trained rabbit dog or two. I much prefer traps. They are a much more efficient use of your time.
There are a huge number of traps that are commercially available to catch rabbits. These traps are baited with food that rabbits like such as carrots. This website doesn't rely on anything commercial because this is about long-term survival and all things eventually break. But a modern trap does serve the purpose of introducing the basic ideas behind any trap and making a wild made substitute will be much easier if you have a design to simulate or modify. So the purchase of a live animal trap can bridge the gap when the SHTF and teach you something about building your own.
Here is information on how to clean a rabbit for food.
How To Clean A Rabbit.