Are there any resources on creating primer schematic diagrams?

Hey all,

I'm trying to create a primer schematic based on the info in a paper because I'm having some issues with them but I'm seriously pulling my hair out because I can't seem to recreate the schematic from the paper's info! I'm trying to use SnapGene but the info in the paper and what it gives me is never the same.

Are there any resources you guys know of, or anywhere I could go for assistance?