How do you make an update.zip?

Wanted to try messing around with this..I tried searching but I didn't see anything just designated to this (however I am sure there is the search just brings up a bunch of rom threads, etc.) Is there a good tutorial that anyone knows of?

 

Here is what I did. I took an update.zip that someone else already made. Used 7zip and opened archive. Cleaned out everything but the basic folders of system, app, fonts. Then I add the .apk files I want in the appropriate folder. This way I am not messing with the whole signing process.

 

Alright here's what I do. Download the lwp that I made.

Open update with wnirar. Open system folder and then app folder. Delete the LiveWallpapers.apk and drop whatever apk you wantthere. Push back twice until u see the system and meta-inf folders. Highlight both folders and right click on the mouse. Click on add to archive and name it update.zip. Done!

If u wanna change the update script (for example, mine say "installing Live Wallpaper", or whatever rom that Team DC releases) open Meta-Inf, then open Com folder, and then open google, then open android folder. open updater-script with notepad++. Change it anyway you want.

LWP update: PanthersUD9.8_update.zip