As a first step we recommend you to read this blog article:
http://www.shutterstock.com/blog/6-tips-to-follow-when-submitting-vectors-for-the-first-time
Uploading
A vector submission requires you to upload two files at the same time: An .EPS file and a small .JPEG version of that same image with the exact same file name. We accept EPS files that are compatible with Adobe Illustrator 10 and Illustrator 8. There is no minimum size requirement for Vector Images, but there is a maximum size requirement of 15 MegaBytes (MB).
The JPEG version has no size limitations but should be at least about 300 dpi.
If you encounter issues uploading your vector files, most commonly the message "Pictures must be at least 4.0 megapixels...", it means that our server was not able to connect the two files and thinks they are separate submissions. To resolve this please make sure to :
1. give the two files the exact same names, like:
vector_example.jpg
vector_example.eps
2. make sure the two files are uploaded at the exact same time. If only one of the two files was successfully uploaded you must remove that file and upload both at the same time again.
3. make sure not to enter the Content Editor by clicking "Edit Submitted Images." until all images are uploaded. If you start editing before all files are uploaded the connection between the two will also be lost.
Submit
Once your vector and jpeg image have been uploaded you will see one image (with the word vector written on it) in the Content editor. Since it is a vector the image is automatically tagged as an illustration/Clip-art.
If the image contains silhouettes or auto-traced elements we require reference or source images to be included in your submission to show us that you own or created all parts of these images.
A reference image can be in the form of a photograph, a sketch or drawing and must be uploaded in the Property Release field along with your submission. Please note, it is not necessary to fill out a property release form, just upload the reference image file in the property release field in the Content Editor. If you are creating the images digitally, please submit a screenshot of the outline/wireframe as reference