Our favorite file formats are, in this order: .ai, .eps., .pdf, .psd, .tiff, .png, .jpg, .gif.
Ideally, you have the original, highest resolution version of your graphic. If you are creating your graphics in Adobe Illustrator, Freehand, or other vector-based software, then you just need to set your document size to the size you want your graphic to be. If you are sending a vector-based EPS or PDF, make sure you convert your type to outlines to avoid missing fonts.
Microsoft Word & PowerPoint documents are especially hard for us to view; if you are using one of these programs to create your graphic, you can export your file as a PDF.
