Cats are often more difficult to find when they aren't where they should be, but rather than walking (or more often, driving) away, there are some things you can try to do to help get the little sweetie home safe and sound:
1) If you see the cat on a busy road, don’t cause a traffic accident -- safely park your car and turn on your hazards so other drivers know to use caution
2) Always consider the safety of the animal first -- if cars are zooming past, any move by you could cause her to bolt into traffic. If you are at all wary of that situation -- stay in your car.
4) If the kitty is injured -- don’t attempt to move her (unless she is in a dangerous place for her safety, like on the road), but rather immediately call for help from animal control. Stay with her until help arrives.
5) If it looks like she will let you pick her up, understand that you might GET BITTEN OR SCRATCHED -- but once you make the decision to pick her up -- COMMIT to it 100% because dropping her will just scare her more and make it even more difficult to recover her later.
6) If you don’t feel that you can safely approach her -- call the local animal control office, give them your location and keep her in your line of sight until they arrive. If you can use a crate and the cat isn’t hostile, consider putting her in a carrier like this.
7) Put the cat in your car, close the door and call for back-up -- call your local animal shelter or animal control office first -- and if she has identification tags, notify the pet’s owner, too. Do NOT attempt to drive the cat somewhere unrestrained -- that is potentially unsafe for you and the kitty.
8) If you are able to restrain her in some way -- large box or if you just happen to have a companion animal crate in your car, you can transport her to the nearest animal shelter.
9) If there are no local shelter or animal control resources available, and no owner information via ID tags, you might decide to take the animal home with you until you can get the animal to the appropriate place. Make sure to go back to the place you found her and put up “FOUND CAT” signs -- as well as post online through social media and other found pet resources -- her family is probably desperately looking for her. As soon as you can, take her to a local shelter or vet to get checked for a microchip and inquire about any local lost cat notifications. Always assume her family will never stop looking for her.