get yourself some asa 400 color print film and shoot the whole roll. No you can't take it out halfway and put it back in. Make sure you wind until you can see number 1 in the red window on the back of the camera ... it takes a bit, be patient.
If you can, ask at the local college or even a high school where they teach photography -- or here's a great idea-- go down to the local senior center -- and find someone who is familiar with film cameras that use 120 film who can give you a primer on using the camera -- it's VERY simple, but if you've never done film you can use a run-through.
I bet you anything you'll find someone at the senior center who used cameras like the holga/Diana when he/she was a kid and will be happy to show you how to use yours in exchange for a cup of coffee and some patient listening.
if ur anywhere near Ogden, Utah, look me up, I'll give you a roll of film and half an hour at Sadie's coffee shop on two-bit street and all you have to do is buy the coffee.--charlie trentelman. I'm in the book.