Lots of wonderful suggestions, but the secret, as was said by all, is practice...completing film tests compelled me to load and process lots of rolls of 120 film. After loading about 5 rolls I lost the "fear", and simply made up my mind that loading the reel was not delicate brain surgery! I usually start with the loose end, put the film into guides on the plastic reels ( I use a Jobo ), and "walk" the film into the reel. I let the paper curl and fall away. If the film gets stuck, then I gently push the film along ( handling by the film edges of course! ) into the plastic grooves until the film is threaded onto the reel. If nothing else works, then I go to the taped end, remove the tape, fold over any remaining tape, and load from the taped end which, with the tape, is more rigid and sometimes easier to get under the guides of the plastic reel. If you get too frustrated, consider putting the entire unloaded roll carefully into the developing tank ( remove the center post of course ), put the top on so the tank is light tight, and go have a beer or walk the dog. It is amazing how the short break often removes any pent up stress, and doubt. Go back into the dark-room, take off the top of the tank, put the post in, and load the reel!
Let us know how you are making out, and the very best of luck. You can do it!
By the way...if you are impressed with the size of 120 vs. 35mm, wait until you develop your first sheets of 4x5 film and compare the detail with such rendered on your 120 film....and then your first sheets of 8x10, and compare such sheets with the size and detail of your 4x5 sheets....:}
Edwin