When uploading images to WC!, please use the WC! Image Uploader or file attachment features. The reason for this is that if your website ever goes down or the images are removed from your site, they will no longer show up in the thread, rendering the thread (or post) and its comments useless.
The size limit allowed for images on WetCanvas! is 800 by 800 pixels. The following links are quick guides and helpful features.
Rezising Tutorial in Photoshop
Creating a Signature Banner
Posting Larger Images