Hi! I've been using the omnipod and had some occlusions in the beginning. I'm not positive what caused them, but there are a few things I changed that stopped them from happening. It's been at least three months since I've had one.
I started shaving the spot I would be placing the pod. I'm a woman, and only had that fine, almost invisible hair on my abdomen, arms and upper thighs, but I think the combination of removing the hair and the slight exfoliation shaving gives helped a lot. It certainly helped with adhesion and removal.
I also make sure I put it on a spot that gets little movement. I got the most occlusions when the pod was on my belly, so before sticking it on, I always contort my body for a minute to check if the spot on my abdomen creases or stretches much in different positions. Some areas may stay smooth while standing and sitting, but scrunch or pull when you reach behind you, or lean over to pick something up.
Of course, too much pressure or bangs to the pod can cause occlusions too. If I put it on my arm or leg, I sleep with a pillow on that side of my body so I can't roll over on it. While it seems safe to lay on the pod while I'm awake, I think the motion of rolling over onto it while asleep was causing problems.