I am only passing on information that I have searched (mainly through Modaco) for and tried and tested. This is by no means my creation or discovery! And also...dont sue me if you mess your phone up!
First of all, you must be rooted!
Best thing to do before installing apps2sd is to do a factory data reset.
There has been discussions on whether apps2sd overwrites the phones factory defaults. I think the problem lays in an old script of apps2sd, perhaps there is a new on out... I couldnt tell ya! Anyhow, this is not really a problem if you want apps2sd permanently on your phone though. So remember, start from scratch, reset your data.
1. Partition your sdcard and make 3 partition on it.
Example: sdcard is 1 GB
1st partition in FAT32 600mb
2nd partition in ext2 300mb
3th partition as swap 100mb
Im not sure if the swap partition is needed but I made it anyway.
2. Copy the apps2sd folder to the root of the sdcard.
3. Connect your phone from ADB and type this command :
su (approve with superuser aplication in your phone)
After a while your phone will reboot.
4. Now check how much internal memory you have (I had 135mb after my clean install of apps2sd. I have never had that much after a factory reset, a hard reset or a flash).
And there you have it folks!