The tips are all folded and glued, and ready to be attached to the base. So now, we have to put that base together.
Trace the outline onto cardstock (or, if you are really smart, print it on cardstock in the first place).
Before you cut out the shape, you need to score all of the lines so that they can be folded very easily. Normally I'd use an embossing tool, sadly, mine (that I'd had in my hand just two minutes before) had disappeared somewhere. Necessity being the mother of invention... I grabbed my seam ripper and used the tip to score all of the lines. After you score them, fold them. Trust me on that, it's far easier to do it now than it is after you cut out the piece. Totally ignore the numbers I've written on this one, they mean nothing, I was just counting the total number of tips I needed to make.
Once you've folded everything, cut out your shape. Apply a small amount of glue to a tab, and glue it where it seems to fold. There is no "tab a" or "slot b" on this, but if you fold the shape the tabs automatically end up being where they are supposed to be.
One of the triangles has no tab on it. That is the last portion I fold and glue. If you're going to hang this, that is the best place to add the hanger. I've made this out of perle cotton, with a great big, seriously large, knot on the end... and a little glue... then I tucked it onto the slot between those two tabs and glued the final triangle closed.
This is what you have once that's all accomplished.
Then, it's time to start gluing your book page triangles to the shape. Don't use an excessive amount of glue or it will take FOREVER to dry (that leads to lots of slipping triangles). Glue, allow to dry a bit, then glue on the next one.
Most of the time you can glue one or two of the flaps directly to your cardstock form, but sometimes you have to glue a point to one that has already been glued. When that happens I tuck one of the flaps on the point I am gluing down under, to provide a "finished" edge
When you do that, hold the point a few extra seconds to make sure it has adhered. Then it should look something like this. Just keep gluing points on all of the spaces, and once they are all filled in, let the star dry well before hanging (otherwise, sometimes you get points that fall off... don't ask me how I know this).
And... there you go... a gorgeous 20 point star.