@reloaded_in_pa brings up an excellent point...you gotta wear it to get comfortable with it.
There are a great many factors which go into comfortably carrying a handgun, and they aren't all the same for everybody. Body geometry, size/weight of the handgun, holster, belt, clothes you choose to wear, the weather, where and how you carry the firearm, type of handgun, activities you are involved in, type of vehicle you drive, and even simply personal preferences.
That's a lot to deal with.
But the best starting point is a solid foundation to be found in a good holster and good belt, specifically designed to properly support your handgun.
Then...you gotta carry it. Especially people new to carrying. You gotta carry it to get used to it and you gotta carry it to figure out if you need to change some aspect of how you carry for comfort and security of the weapon.
With respect to wallets, which was brought up, over the decades I've discovered some secrets to this as well.
Probably one of the biggest for wallet comfort is to keep your wallet trimmed down. I don't know about the rest of you, but over the course of a very few short months my wallet can accumulate a lot of junk in it. Scraps of paper I've scribbled notes on, business cards I've picked up, credit/bank cards, pictures, various ID cards, store cards, restaurant cards, and more. It's simply amazing how much junk you can pack into a wallet and it really affects its bulk.
"Gee, Chief, how many ID cards to you have?"
A great question...driver's license, concealed carry permit, and my retired military ID.
Toss in two credit cards, an ATM card, government travel credit card, firestone card, my insurance card, and a couple more credit card sized cards for a couple places and the cards start getting thick. Hunting/fishing licenses for two states, etc, and it adds up.
I periodically thin my wallet out. Many things, like my store cards (Best Buy, Firestone, grocery store, and various restaurant "buy 10 meals, get one free" punch cards) I simply pull out and keep in my car somewhere convenient. Scrap old notes and whatnot. I don't carry pictures in my wallet any more, either. It is AMAZING how much that thins your wallet down.
My wallet is a Buxton double ID passport wallet (28826), which has a small removable folding "passport wallet". I keep my drivers license/retired ID in it and whatever credit card I feel is important. When I really need to slim down, I pull this out, put the rest of my wallet away, and simply carry that. There are several wallets out there which are excellent options for minimizing your wallet footprint.
Another thing: Not all pant pockets are the same. And you don't always have to carry your wallet in the back pocket.