There are a lot of ways to make photo block puzzles, but I will show you how I have found to make them easily and inexpensively. My method is just one way, but I like it the best of the other methods I've seen.
4 blocks for every puzzle you are making.
I prefer to use 2 inch blocks and make a 4 " x 4" square puzzle. You can order 4 x 4 inch square prints pretty inexpensively online via Walgreens, and other such stores for less than 50 cents each usually and I think the finished size is nice. any larger is too large a block for toddlers, (if that is who you are making it for) and 1 inch blocks seems to small for me. so I just like the 2 inch size.
I prefer just to order the blocks. I order them through amazon in bulk, but you can make your own easily. You can get a strip of 2 inch square lumbar at any big box home improvement store and they will even make the cuts into 2 inch blocks for you for a small fee. You'll just need to sand the blocks down to make them smooth.
I prefer to cover all 6 sides of the "puzzle in photos. but you don't have to. You can cover other sides with decorative paper, or even one side could have 4 individual 2 inch photos on them. Lots of options!
I usually use Walgreens because they are close by, I can upload my photos online, and edit them before hand to see how they'll turn out first, Also I wait to use a 40% off code, so instead of paying like 39 cents each I pay almost half that. I'm telling you.. for a specialty sized photo, you can do this very cheaply! I paid only like 25 cents total for each of the 6 photos I used. Then I just picked them up at my convenience. But you can play around with using photos you have on hand and cutting them down to fit your blocks. I just didnt' even want to mess with it, so ordered photos to fit.
Jan's Tip: I found photos with 2 people where they had "put their heads together" in photos didn't work as well as photos where there was a little space between their heads. It helped when I had to make the cuts in the photos I didn't slice right through their faces as much. I still had to in most photos somewhere, but in photos where they put their heads together it didn't work as well.
To buy or to make: I know, the brand is so expensive! I've made my own with glue and water plenty of times... But this is a gift.
I prefer to use a coupon to a craft store for 40% off and go buy it and get the gift done well and not take a chance my photos will start peeling off. But that is just me. I prefer the matte (Non shiny) finish. The photos already have a gloss to them enough as is.
Photo Block Puzzles
4 (2 inch wooden blocks)
6 (4 inch) photos
scissors or paper cutter/ruler
If using a paper cutter with a built in ruler, if using scissors and pencil turn photo over and measure over two inches from edge in both directions on back of photo.
Cut photo in half at 2 inch mark to make 2 even strips.
Cut apart each strip the other direction at the 2 inch mark to make perfect 2 inch squares.
Using foam brush apply a thick even layer of Modge Podge to 1 surface of each of the 4 blocks.
On work table lay out your photo pieces in the order they belong as "finished" puzzle. This is how you need to apply them to the blocks.
In keeping track of how the puzzle should go together, 1 by 1,carefully place the photos onto the blocks in the exact order they should be when the puzzle is completed, lining up the photo with edges of the block and gently pressing to remove any bubbles.
Apply all remaining photos to all remaining sides, just carefully turning the blocks upwards or right, left etc. to the next side to apply the next photo.
Once all photos are applied, start applying a top coat of Modge Podge. (IT DRIES CLEAR!) to all sides. a thin layer is fine, but pay particular attention to the edges of the blocks/photos. Let dry between coats. It dries quickly.
You are done!
You could also make a wood base exactly 4x4 inch and then have some small molding cut at an angle to be glued around the edges to create an edge to hold the blocks in. These cuts could all be done for a small fee at most large home improvement stores.