I put a slight reverse crimp in the end of 120 film before loading it (in Jobo or Paterson reels). That stiffens the end and makes it easier to feed evenly for the first turn or so. I also unreel the film as I go. A tangled spiral of film and backing paper is no fun.
For me, loading got a lot easier after I discovered that I was squeezing the reel too much. Now, I just hold it very gently. Easy does it!
I use AP reels, and have had some problems loading them. Normally it is because of moisture building up inside my changing bag. My reels can be changed from 135 to 120 (as most reels probably), and I found it worked better if I pulled lightly on the edges of the reel. That usually helps.
I use paterson reels (that are similar afaik) and sometimes the film can jam, i first try sharply tapping the reel on a hard surface, and then sort of wiggling the spool edges gently, seems to work. But the main problem with mine was dirt on the bearings that pull the film round, worked much better after I cleaned it with an old toothbrush.