you could make a cast on sampler.
cast on 20 to 30 stitches (cast on A)
then work an inch of ribbing, then an inch of stocking knit.
break yarn and put aside
cast on again (cast on B) same number of stitches
work an inch of ribbing.
then hold knitting A (front facing you ) and knitting B (front facing you, and knit them together (sort of like 3 needle bind off, but don't bind off.
work an inch of stocking knit, break yarn, and set aside.
start again with cast on C...
same deal as with B,
then cast on D
don't forget to make a chart (A= Long tail, B=twisted long tail, C= open/closed long tail, D=long tail in ribbing, E=. F=. an so on.
when you're done, you'll have something that looks like this--use it to compare and contrast cast ons...