making the best of it

Not the prettiest picture, but if you cut off the end flap of a 120 film box and fold it just so then you can use it as a film tension-er under the take-up spool as shown below.

I use this little trick in all of my Holgas and it seems to help with avoiding "fat-rolls" which cause light leaks.
Some people use the little flap trick on the supply side as well. 
Newer Holgas have foam under where the film spools go as seen below. 

The foam works great until it doesn't. It notoriously comes loose and will wind itself into the film roll when you least expect it. Then you have a "fat-roll" problem of epic proportions. Not good and an absolute fail.

So if you have an older Holga, or a newer one, try the folded paper trick and see how you like it. 

Periodically I'll share some more of my tips for using the Holga. I really like the simplicity of the camera. Not worrying about settings gives me more time to think about composition.