I've done it where every so often when I think it is warranted the group levels up. You could also follow the Pathfinder Society rules of every three adventures you get to level up too
I really go back and forth on this. The simplicity is nice, but I HATE that there's no distinction between a lackluster performance and an exceptional one, both for individual characters and the group. While I'm exploring a lot of ways of ramping down the complexity in systems I tinker with, I don't think I'm ready to pitch XP entirely to the curb quite yet.
On the other hand I'm also fiddling with more non-XP rewards, so maybe if those systems become robust enough the XP can be a 'given' for just surviving and the other rewards can be used to distinguish between a D and a B+ performance. I should pull together a rough draft and post it over in LtI (to the sound of crickets likely, but I'm getting used to that
The first part of what I said about just telling the group to level up was because I had a simulationist in my gaming group who would get really irritable if someone got more XP than him. He never threw a tantrum but I got some serious negative vibes from him.
One time it even happened while I was running a LSpy mod when I had a NPC disarmed his Character then purposefully break his gun. "We get it! You win okay!" He was playing a Soldier and they faced off with some martial artists. One of them ripped his handgun out of his hands then slid the top of it before dropping them to the ground. He got really pissed and realized he could get his ass seriously kicked. It was the first time I ever saw him choose, as a Player, to have his Character run from a fight. .. The other two Characters, a Snoop and a Scout, stuck with the fight and eventually prevailed. They managed to get rid of the minions then proceeded to go with the Snoop flanking and basically taunting the villain while the Scout circled to take advantage of the flank and get in an attack. Three rounds later, with plenty of sneak attack damage, they prevailed.
Do I like giving out XP? Yeah... I even give out on the spot for figuring out ideas or solutions that rest in the background without me having to draw attention to them. For instance, the Characters discover an unused pulley hanging in a slim alcove and one of the Players voices the idea that it might have been a type of dumbwaiter that was installed. Give that man 100 XP on the spot. It prompts people to do some investigating without me saying anything else.