I am no expert, but I have done this a few times before. First, you will need a good "carpet knife". This is nothing more than a very, very, very sharp razor blade used specifically for cutting carpet. You can probably purchase one at HD, but I bought mine at a carpet supply house (a place that sells things for carpet installers).
You start by pulling the carpet up from the "tackless strips" that run around the perimeter of the room. You can usually do this by hand in a corner. You need to gently pull the carpet until you can get a good grip on the underside. Then gently applying pressure toward the wall, you can pull the carpet off the tackless. Tackless strips are thin wood strips with small brads that point toward the wall. By applying force toward the wall you can get the carpet up. You will pull the carpet away from the wall and roll it back on itself to give you the room you need for your cab. install.
Next, you remove the tackless strip from the sub-floor. This is done by simply prying it up. It is nailed down to the sub-floor with about 1" brads. If you are very careful, you can reuse this tackless strips. Just go along and pry one brad at a time to avoid breaking the tackless.
Now you install your cabinets with the carpet rolled back and tackless removed…....
Now, you can cut-in the carpet to fit. This is a delicate process that needs to be done slowly and carefully. I flop the carpet back up against the cabinet and make a small incision on each side to mark the cabinet. The carpet should be flush with the cabinet front. Then flop it back over to make your cut on the back of the carpet. You should use a good straight edge and line it up with your incisions and then run the very, very, very sharp carpet knife along your straight edge. Be sure to use extreme caution with this knife.
Next, you will reuse the tackless strips to outline the perimeter of you new cabinets. Make sure the tiny brads face toward the exterior of the room and cabinets…. You simply nail these down to the sub-floor approx. 1" away from the wall and cabinet.
Finally, you flop the carpet back over and push down on the reinstalled tackless strip. There is a "kicker - carpet stretcher" tool that pros use to install carpet. This isn't necessary in my opinion, for your small job. The idea is to pull the carpet as tight as you can across the floor and seat it on the tackless. Then use some tool to tuck the carpet fibers in for a neat job.
This is a very wordy response, but I hope it is helpful. You should be able to handle this job. GOOD LUCK!
