Selling Graphics at iStockphoto - Steps to Respect
As I see it (I might be wrong), all the steps above (except reading the guide) should be done in a row or else you should start from the beginning, so before I start the first step I had to have the last one already done (i.e., my 3 sample vectors ready).
Let's talk a bit about vector requirements: in the guide you read before starting your application, you'll be told that with each vector you submit you need to send a JPEG preview sized to a minimum of 1900 x 2800 pixels, as I understood that, it's 1900 px (minimum) width x 2800 px (minimum) height. In fact no! Reading a thread on their forum, I found out the important is pixels number in the preview: 1900 x 2800 = 5320000, so if the value of your file's width x height equals or is bigger than 5320000 pixels, your preview will be approved.
The good news (I think) is that you don't have to send those huge previews with your three required samples when you apply, but only a JPEG thumbnail of 250 pixels width / height maximum.
The vectors themselves (samples & I guess others too), should be PSD files, Adobe Illustrator 8.0 compatible, included in a folder & compressed in a ZIP file.
Now as they seem to have too many requests, you'll have to wait up to 14 days to get a response by mail regarding your application (time to be patient & to have faith).
Too many boring stuff, but that's it if you want to be part of iStock :)
OK, if you still not a member I hope you don't mind I invite you to join using my link (you may refuse my invitation of course).
Good luck & please wish me luck :)