Bought me some plexiglass from Lowe's. 24x48. Had them cut in.half for two 12x48.

Gonna get a bit for plexiglass. Gonna bolt n washer to wood.

My blinds are pretty used, have been just open. Looking for easy way to stay a little warmer.

I'm.open to step by step direction as to how to make a frame. I am far from.a carpenter.

I use plexiglass windows and cut them to fit channels cut in upper and lower 2x4s. I can slide them as open or closed as I want. I cut the plexiglass on my table saw, but put 1/4 inch plywood above the plexiglass to reduce the chance of shrapnel. I am very very careful when cutting that stuff.

I just sandwiched them between 2 2x1/2" or so and nailed them with a finish nailer. Almost zero cracking, and it was fast.

I've made many a frame from 1x2s joined with a Kreg jig. Look it up on youtube, it's really simple, and holds very very well. Just a rectangle made with 1x2s, put a little bead of silicone between the glass and the frame, and don't overtighten.

I wouldn't drill the plexiglass. Build a wood frame with a channel that will hold the plexi.

If your blind allows it, buy 3/8 metal channel (or whatever size is slightly larger than your plexi) and line one side with self adhesive felt or other soft material. Attach 3M Velcro to the top of the glass and the opposite side to the blind. Window will slide up and down in the channel and Velcro open.

I built a frame of 2" x 2", then drilled over-sized holes in the Plexiglas. To cover, I used strips of 1/4" x 2, also pre-drilled, instead of washers. Be sure not to overtighten. The wood helps distribute the pressure over the entire area around the hole through the plexi. Be sure not to over-tighten.

Building the frame just required cutting the wood to length, then gluing and fastening with a long screw through the side of the butt joint. (imagine an L shape, with the two pieces of wood overlapping ends) A corner clamp will help hold the pieces square while you put a screw in.

Here is a clamp: http://www.lowes.com/pd/IRWIN-QUICK-GRIP-3-in-Clamp/50168499

Or, one of these can be used, but is more finicky: http://www.lowes.com/pd/IRWIN-QUICK-GRIP-3-in-Clamp/50146732

I always first tape where I want to drill or cut with blue painters tape, that way it is easier to mark for locations. Leave the plastic coating on until finished. If drilling holes use next size up from bolt size, want a little play, use a sharp drill bit, use scrape wood under, slow speed on the drill motor, do not over tighten the bolts, use flat washers,
I didn't build a frame, used a piano hinge on top bolted to plexiglass then screwed into blind, open outward. Drilled a hole centered in the bottom about 1 /12" up, used some string through triple knot inside, drill hole up from top of window through blind run string through to inside make a loop pull to open tie off.

I build frames from 1x2's with 1/8" plywood spacers and "float" the plexiglass in the frame. Hinges are mounted to the frame, not the plexiglass. I've taken my measurements to Lowe's and HD before and both places have made all the cuts for me.