My high school shop teacher told us to use a thin dime, and if we didn't have one, to use two nickels.
You should reference a manual or internet video to see how. It would be hard to explain without visual aids.
Dave
The spec for most points is .028" I believe. I could be wrong on that as I'm just going by memory. I usually set new points as wide as I can so that I don't have to reset them right away again as they wear in. Make sure you use the lube that's provided.
If you want to go electronic Pertronix makes two different models that fit. Their Ignitor is part number 1145A and the Ignitor 2 is 91145A. If you Google Pertronix the web site will tell you all about it. I've used them on several different engines with good success. If you Google the part number then you'll find them for sale on line.