sander
I have a 1/2 sheet pad sander and I can't find the user manual online.
Sears Craftsman Model p11616.
I also can't figure out how to attach the sand paper. It us designed to use adhesive and non-adhesive backed paper.
Below is a picture of the clasp to secure the paper and I can't make sense if it. It is just shredding the ends of the paper. I can't find a logical way for the full width of the paper to be secured.
The holes on the discs may not line up with the ones in the base--if they don't, you'll have to be careful. As you say it will interfere with air flow, which will affect cooling, sanding, and sawdust removal. I'm not sure whether it's enough to damage the tool, unless maybe if you're sanding for hours, but the results may not be as good..
If you do use them, I would recommend cutting off the excess edge--it can dig into your piece and leave marks.
Release the paper-clamp latches. There will be one or two latches on both sides of the sander. For that model, they probably look like this (note the 2 red arrows, showing the release motion):
Pull the folded-over edges, of the sandpaper, out from under the clamps.
That model may use velcro paper, so expect that you might have to peel the sandpaper off of the base plate.
Replace with the same style and size (length/width) of paper. Assemble in reverse order. Pre-creasing the folded edges works best for getting the edge under the clamps.
You can find manuals at http://www.makita.com/en-us/Modules/Service/ServiceCenters.aspx.
Here is a manual for a similar palm sander (pdf) (AKA "Finishing Sander").
Best Answer
When rotated, that lever should lift the bar it is mounted to. You then slip the edge of the sandpaper under the bar and rotate the lever back, the bar will pinch the paper under it. Pull the paper taut and repeat on the other side of the sander to secure.