In my case, this costs about $0.25 USD for a 50-page booklet, when accounting for the cost of printer paper and ink.
Once your booklet is printed (make sure that it is printed double sided, in landscape orientation, and flipped on short edge), maintain the current order of the printed stack of papers.
If you've printed it in the correct order, then you should be able to fold the entire stack like this:
You don't have to be too precise since the margins are pretty big.
From here, you want to staple the pages together. This is done by laying the stack of pages flat out, making sure they're at least somewhat well-aligned.
Place an eraser or object of a similar consistency under the paper at the spot you intend to staple. This gives the stapler a surface to staple into that won't destroy the staple like a desk would:
Staple vertically along the crease. Two staples is all you need for booklets of this size. You don't have to be too precise with alignment, but try to be in the general area of the center crease so that the booklet can be flipped through. If you staple badly, you can easily pull out the staple and try again.
When you've stapled, pull the eraser out of the staple and push the arms of the staple down with your fingers so that it can hold the papers together, as seen below:
Repeat this process for the second staple on the other edge of the booklet and you are finished! You can re-fold the booklet along the crease in order to make it stay shut better. You can also put it in a stack of books or under weight of some sort for a prolonged period of time to make it stay shut better and be easier to flip through.