I purchased some of these a while ago.

I have not used any film with them yet, but I do have a couple of ideas on how to use them more effectively.

I am more impressed with the macro, wide angle, and closeup lenses.

I have a 120 slide frame that I have sandwiched 2 layers of wax paper between them to act as sort of a ground glass viewer to be used at the inside focal point of the camera in bulb mode without the camera backing before putting film in it; this could be done with either 120 or 35mm.

You could likewise make the a frame out of cardstock with the wax paper and before you put film into your Holga, check the various focus distances of each of your closeup or macro lenses measure what looks and focuses best and write it down. Then use a marked measuring cord with those distances from the lens or a tape measure if you plan on using your closeup or macro lenses.

When using your Tele lens, I do not really know any tips for these, but I noticed it works best at making something at about (3m) 10 feet away look to about (1.5m) 5 feet away, while keeping some detail in the image. Distant images will not keep as much detail when using the tele lens.

So in my opinion, the tele lens will perform best just when you are a bit closer to your subject, for example a bird, or a squirrel in a tree at about 15 feet away, which is probably just what this little animal might find as a safe distance from you might be before taking off, but the lens will bring it 2.5 times closer.

Centering the image will also be more important when using all lens addons, because the vignette will be stronger by using these.

Just make sure your having fun with them.