Here's the easiest route that I'd take and suggest:
Step 1) On your Manage Domains page in the panel, click "Edit" next to soakupthefun.com and make it Fully Hosted rather than a redirect. In the Fully Hosted settings, make sure to host it on the same user bethcordi.com is on.
Step 2) To minimize downtime, I'd wait until you can access soakupthefun.com as a fully hosted site (in case DNS propagation takes a little time at this point) before step 2. Once you can reach soakupthefun.com and see the "Coming soon!" page we put there by default, log into your WP dashboard at bethcordi.com/soakupthefun/wp-admin. Go to your general settings there, and change the URLs to be http://soakupthefun.com rather than bethcordi.com/soakupthefun.
Step 3) Connect to the server with your FTP user (or via SSH) with an FTP client. Drag the sub-dir bethcordi.com/soakupthefun back out/up two levels to your user directory. Once there, you can either move all the contents from it easily into your new soakupthefun.com directory there, or better, just delete the new/blank soakupthefun.com dir and rename your /soakupthefun dir to soakupthefun.com. Alternatively, you could just copy all the files in bethcordi.com/soakupthefun/ and paste them in the existing soakupthefun.com directory. Whichever route you prefer, you should end up with all your WP files in the soakupthefun.com dir there.
That should be all that's needed. In some cases, if you're using a heavily customized theme that has your URLs hard-coded in any places, you'll have to go through and manually update those links to use the new URL.
Additional info on moves and troubleshooting can be found here as well: http://codex.wordpress.org/Moving_WordPress
I hope that helps!