On the one hand, I want to help, on the other, no one taught me and I was able to figure it out on my own, so I'm probably going to be a bit *****y.

First, you need an account on the maemo.org garage - I think it's the same as the rest of www.maemo.org (excluding talk.maemo.org of course) - if you have one great, if not, make one.

Then you need to go to the Maemo Extras Assistant and apply for upload priviliges. https://garage.maemo.org/extras-assistant/ (It asks you to login, then if I recall correctly after you log in, it'll place you on a page saying you don't have upload permissions, and there should be a link right there to apply for them. If not, power search on the wiki for "extras upload" or something is your friend..).

Anyway, after you apply you wait a couple of days, until you get an email saying your request has been granted (presumably it would be).

Then you go back to the above extras assistant page linked above, log in again (or it might remember you still) and go to the next step whereupon it'll let you upload the source packages. (It'll want the .dsc, .tar.gz, and .changes files - the necessary dpkg-buildpackage parameters to generate those files are listed (for scratchbox at least - which shouldn't matter other than -rfakeroot being changed to -r[whatever root command you use in your build environment]) on the upload page.

Then you wait. While the thing builds, and _eventually_ imports to the -devel repo. Then you promote the packages from the maemo.org/packages interface (promote the armel build, if there is one the i386 build will auto-promote with it). The best part of the waiting though is when you want to get something down into Extras from Extras-Testing, because you get the joy of waiting for weeks until the measely ten votes acrue to get your app promotable to Extras. EVERY time you have a new stable version mind you.