I have been pilling cats for 20ish years, and I have gotten to the point where I feel pretty comfortable pilling pretty much any cat.
I'm careful saying that, as I remember fully years ago when my Tiger got an abscess. After waiting way too long past my scheduled appointment to see the vet, the vet told me I needed clavamox (which I so knew because Tig had many abscesses by that point) and had brought in a pill to pill him. I warned the vet that Tig was not an "easy pill" and he dismissed me and proceeded to give the pill. Well Tig was annoyed by his arrogance and ended up biting him so hard he drew blood. I couldn't have been prouder of my boy in that moment.
Anyway.. This is what I do..
The first and most important is the grab of the head. I am right handed so I use my left hand, I wrap my hand around the top of the cat's head, keeping my thumb on the right side
I then slip my pinkie behind the head.
This has the effect to keep the kitty in place. You know how cats try to 'back out' of any situation, and you often have to wedge them against yourself to keep them from backing out of getting pilled, well for most situations and most cats, this covers that need to have someone hold or keep them from backing up. It isn't perfect, some cats still try, at which point I'll stick a foot, or a leg if I am sitting down, behind the cat.
Next is to lift the head up and point the nose directly to the ceiling. Doing this will cause the mouth to open slightly..
At this point you have a straight shot to drop the pill down the back of the mouth (aka right in front of the roof of the mouth) and have it land in the throat. Sometimes you'll do it first shot, but some times you need to stick your finger in the mouth to push it in past the "hump" of the tongue. This is where my last trick will help a lot.
|Insert "pill" here please|
You slip your thumb down into the mouth - but you bring a little bit of the lip with you. This is not painful for the cat UNTIL they try to bite you.. Once they start to bite down it will feel uncomfortable for them and they'll stop. This prevents you from getting bit, and will give you a few extra seconds to get your finger in there and push the pill into the throat.
Make sure you follow up with a LOT of praise and love and food. "Dry pilling" which is what this is, can have the side effect of the pill getting stuck in the throat and causing some severe irritation which can then lead to vomiting and anorexia. If your kitty won't eat, then using a syringe with a little water to force the a little water into the mouth and cause some swallowing will help. Your vet can provide you a needless syringe for just this purpose or you can usually get one at your local pharmacy, or even in the infant department at most major stores.
If you want you can and probably should practice pilling your kitty with treats. They will be more inclined to let you do it because "fails" will be yummy for them. It will also give you a little bit of an advantage when the time comes as you'll have experience and your kitty will be expecting treats.