How do I upload multiple files at a time?To upload multiple files at the same time you can create a set then select the multiple files you would like to upload from your computer (by selecting all) then 'Open', or with the third party app Scup (http://soundcloud.com/apps/scup). These files will automatically upload and create a set.
If you forgot one, you can click 'Add new tracks' like in the image above!
Note: If you would like to upload multiple files but do not wish them to be added to a set, when uploading a file to SoundCloud, just select all the files you would like to upload on the upload page at once and open them. The site will then attempt to upload all the files selected.