I’m using GIMP, should I export as a jpeg? a png? im not completely sure, I appreciate your help thanks! 
When in doubt save in multiple file formats. I prefer Lossless formats like Tiff or EPS format. PDF and PSD are also good as most print shop use Adobe Photoshop formats.
JPEG and GIF should be avoided as its a compressed format, and it does create alot of visual artifacts or distortion. Save in JPEG only if you have to. Avoid GIF like the plague.
It also hugely depends on who and where you are getting your art printed by. If I was you, I would save in PNG, TIFF, PSD, PDF and bitmap or BMP format (even though the resulting file will be huge).
PDF is lame because sometimes you run into color-conversion and compression issues.
For upload online I’d stick with PNG. For printshop-use I’d use a flattened PSD (all layers merged) or TIFF or PDF (but only if they ask for it that way).
If you want to print it out on paper make sure you’ve set color to CMYK. For web or online it’s RGB with embedded color profile.