1. Download the rom to the SD card.
2. Make backups of your user apps and data with titanium backup.
3. Boot into recovery.
4. Make a backup of your current rom in recovery using nandroid.
5. In recovery do a factory reset/wipe data.
6. In recovery wipe cache.
7. In recovery wipe dalvik cache (under advanced)
8. (This step is not always needed but I suggest it for DT's roms) In recovery format /system (under mounts and storage)
9. Install zip from SD card, choose zip and navigate to it, if you download the rom from the dev on the stock browser it should be located at /sdcard/download/
10. Wait until it finishes and reboot, let it sit for a while for the initial boot and then sign into google and start restoring your backups.
Edit: I do not use the data cable at all. You can verify your download using the MD5sum which is ususally given by the dev and can be found on the phone using AFV(android file verifier) from the market.
2. Make backups of your user apps and data with titanium backup.
3. Boot into recovery.
4. Make a backup of your current rom in recovery using nandroid.
5. In recovery do a factory reset/wipe data.
6. In recovery wipe cache.
7. In recovery wipe dalvik cache (under advanced)
8. (This step is not always needed but I suggest it for DT's roms) In recovery format /system (under mounts and storage)
9. Install zip from SD card, choose zip and navigate to it, if you download the rom from the dev on the stock browser it should be located at /sdcard/download/
10. Wait until it finishes and reboot, let it sit for a while for the initial boot and then sign into google and start restoring your backups.
Edit: I do not use the data cable at all. You can verify your download using the MD5sum which is ususally given by the dev and can be found on the phone using AFV(android file verifier) from the market.

you went from being weary of rooting to rooting a friends phone and restoring his contact back, soon you will be posting here more than me 