How do I post a drawing image

[jgmick]

Read thru several posts on guidelines for the forum. Didn't find this one.
I want to put up a post on some things I have been making (cooling grilles for an excavator). With that I would like to include some small drawings to help illustrate the stuff. I can make the drawing images into anything (jpeg, pdf, wmf, whatever.) Should I just convert them to images and put hem in with the pictures or is there a different way to do them?
Guidance needed.