Cats are much safer indoors--that's a fact. Indoor cats generally tend to live longer also. Unfortunately, there are many stray cats roaming the streets that need homes--and we're not always equipped to take them in--or they may not want to be taken in. A domesticated cat that's used to people will be ready to be placed in a home, whereas a feral (untamed cat) that's used to the streets will most likely not be. In any case, here are some ways to care for and protect stray cats until they can hopefully be placed in forever homes.
Instructions
Set out dishes containing cat food and water, in a covered area if possible. If it's before you can get to the store and the cat appears to be hungry, offer some pieces of chicken or other type of meat and mix it with rice if you have some. Tuna is OK too, but in small amounts. If you feed the cat, the cat will likely return.
Make sure there is a covered, protected area for the cat to go in case of extreme temperatures or rain.
Call shelters in your area to see if the cat was reported missing. Post a free announcement on craigslist, petfinder.com and/or in your local newspaper's lost and found section in case the cat has owners. Wait a few days for a response before trying to get the cat adopted. If someone does respond, ask specific details about the cat that weren't included in your ad, so that you can confirm this person, is indeed, the owner.
Research online for no-kill shelters and cat rescues in your area. Chances are shelters may be full and have waiting lists, but you never know, and should call anyway; they may have some alternative suggestions depending on where you live. Your best bet, however, is probably with independent cat rescuers, who, even if they are full, will network and get the word out.
Get a pet carrier and schedule an appointment for the cat to be examined, vaccinated and spayed or neutered. That is if the cat is friendly and used to people, otherwise you may have a hard time. Check online for low-cost clinics in your area. Spaying/neutering is crucial for helping to control pet overpopulation and curbing a male cat's urge to wander. It is also healthier for the cat. (See link in Resources below on how to trap and care for feral cats.)
Take a few pictures of the cat and ask one of the rescues or shelters if they could help you by posting the cat's information and picture on Petfinder.com and AdoptaPet.com (see Resources below), websites that list thousands of pets available for adoption throughout North America. (Individuals can't list pets on AdoptaPet, but rescue organizations and shelters are able to list under their name. Petfinder allows both rescue organizations and individuals to post pets up for adoption) Thousands of people search this popular website, and you never know, this may be just the cat that someone's looking for.
Make a flyer with the cat's picture and description to put up at local pet stores and vet's offices that have bulletin boards featuring pets in need of homes. If you have any doubts about a prospective adopter, make sure you visit the home where the cat will be living first. It's also a good idea to charge an adoption fee (or say there's an adoption fee) to weed out any unscrupulous adopters who would put the cat in danger.