Conducting Ongoing Trap-Neuter-Return
After you have successfully trapped, neutered, and returned all cats in the colony, keep an eye out for any newcomers. Ear-tipping is especially important in this regard as it will help you easily identify which cats have been fixed without having to approach them. Immediately TNR any new cats.
Keep accurate records of all cats in the colony and enlist the help of neighbors to inform you of any problems or changes. This will also help to promote the positive results of Trap-Neuter-Return. Take care of any injured or sick cats immediately. This will help prevent the spread of disease from malnourishment.
If there are kittens old enough to be separated from the group, start a plan to socialize them to humans and find adoptive homes for them. The same goes for any adult cats in the colony that are human-friendly. This will help to shrink the number of cats humanely. More information on socialized cats and feral kittens can be found here.