Google provided plenty of developer tools to generate the different types of OTA. If you want to generate a Full Update OTA, the following two steps are required:

To generate the zip file containing the chosen target files, navigate to the root folder of the AOSP sources and run the following commands:

. build/envsetup.sh && lunch aosp-shamu
mkdir dist_output
make dist DIST_DIR=dist_output

If the process has been successful, we should have the zip file containing the target files in the directory dist_output. As an example, let's try listing the folder content with the following command:

ls -l dist_output/*target_files*

Now we should see a .zip file that will also have in its name the name of the target we are compiling for.

At this point, you only need to generate the OTA package containing all the necessary files for the update....