From the organizer, you control what's in your repository and what's on the wall.

To begin, go to the organizer and hit the sign in/out... button. That opens a secure popup window so you can sign in. Sign in using your artist account username and password. You can close the sign in/out window until you are ready to sign out. You will be signed out automatically after 3 hours.

Next, click the get current state (or revert) button to get the current state of your part of the wall. At first, that will be nothing, just a blank grey page, but you can easily change that by adding some image files to the repository and adding some of those images to the wall.

Changes you make in the organizer—except for uploading files—do not become permanent until you hit the save changes button. You can always revert to the last saved state by clicking get current state (or revert) instead of saving. If you leave the organizer web page, any unsaved changes will be lost.

The repository is the place on flat grey wall's server where your image files are kept. It includes images currently being displayed on the wall, and possibly many that are not. You can show up to 35 images on the wall at a time, with another 100 or so (depending on their file sizes) in the "back room".
To add files to the repository, open the upload popup window by clicking the upload... button (above available files in the organizer). Browse your local drives for a file and upload it.

Allowable file types are .zip, .jpg, .gif, and .png. Most artwork is best displayed as .jpg, and you can upload single .jpg (or .gif or .png) files directly. The best way to upload multiple files is to create a .zip archive and upload the archive. The organizer will unzip the archive on the server and process its contents as if they had each been uploaded separately. It will even preserve the archive's folder structure. Most modern operating systems have a built in ability to create .zip archives; see your system's documentation for the details. If yours doesn't, gzip is free, open-source, and probably has a pre-built executable for your OS.
After an image file is uploaded, it is processed as follows. Two images are created, a thumbnail whose longer dimension is 130 pixels, and a larger image whose longer dimension is 700 pixels. If the longer dimension of the uploaded file is smaller than those it is not scaled up, but if it is larger it is scaled down, so it's just a waste of bandwidth to upload files with a larger dimension much greater than 700 pixels. Files in compressible formats are compressed to a quality of 50/100, so you shouldn't compress them to a lower quality, because they will still take the same bandwidth to view as the higher quality, and will contain all of the compression artifacts of the lower quality. One more bandwidth issue: if you use Photoshop to create your images, you should use "Save for Web...", not "Save As...", because the latter adds about 50K of useless data per image (which is stripped out during conversion, producing thumbnails ~4K instead of ~60K).
To remove files from the repository, condemn them. Condemning a file marks it to be deleted on the next save. Any time before saving, the file can be uncondemned, and get current state (or revert) will uncondemn all condemned files. The organizer will not let you condemn files that are currently on the wall.
Available files is a list of all the files in the repository, with the following color codes.

• blue: not on the wall
• grey: on the wall once
• pink: on the wall more than once
• dark grey: condemned

When you select an item in the available files list, its thumbnail appears above the list. To add that image to the wall, click the ADD button to the right of the thumbnail. Below the ADD button is the condemn button.

All images currently on your part of the wall appear as items in the on the wall section of the organizer. Each item consists of a thumbnail, some information fields, and some control buttons:


To add an image to the wall, select it in the available files list, then click the ADD button to the right of the thumbnail that appears above the list. A new item will appear at the bottom of on the wall. Fill in any information fields you care about.
All non-blank information fields except quantity available will appear in the image's caption. You are actually free to use the fields in any way you wish, with one restriction: if you want to sell things using the PayPal cart, the price must be the pure number price in USD (no leading '$'); if it is, and quantity available is a whole number greater than 0, a buy button (linking to the cart) will appear beneath the large version of the image.To remove an image from the wall, click its remove button.
To change an image's position in the order, click its change number button.
To replace an image on the wall, click it; it will be replaced by the currently selected repository image (but the information fields will be unchanged). To undo the replace, click it again.
Image number 1 is also the 'preview image': the image that represents you on the wall of previews.

None of the organizer controls take you away from the organizer—losing unsaved changes—without giving you the opportunity to cancel.

We dislike exclusion and coercion. Many online galleries will exclude work on the basis of a whole panoply of ill-examined aesthetic prejudices, or force you to meet certain 'minimum standards' of presentation. We try to avoid both. For a while we tried assigning each link on the wall a color value reflecting our idea of the work's quality, but decided we dislike that just as much. It's up to you, but we suggest the following. Images should be in focus. Paintings, drawings, and other rectangular objects should be aligned with the edges of the image and cropped. Colors should be corrected to accurately represent the objects. There should be no color cast.

Google, the search monopoly, ranks search results largely by counting incoming links, so if you know anyone with a web page or blog who likes your work, ask them to link to your page. This indirectly benefits everyone, since each artist's page contains a link back to the flat grey wall root page, which in turn links to everyone on the wall.