To get started with Android, you'll need to get familiar with Git and Repo.
To initialize your local repository using the IceColdSandwich's trees, use a command like this:
repo init -u git://github.com/IceColdSandwich/android.git -b ics
Then to sync up:
repo sync
To build:
. build/envsetup.sh
lunch htc_ace-eng
make -j4 lord
OR if you have ccache app installed than it's better to use this script:
. vendor/lord/build.sh