The way I learned it was just by listening to punjabi music. Basic playing (like Chaal, Bhangra, Giddha) are in majority of songs, but try different variations of them. For example, in 'Bhangra' (Dha NaNa Ge Na) try adding another 'Ge' to make it sound more full and rich -- Dha NaNa GeGe Na. You can even add more bass hits to make the beat sound different so you can extend the beat.
If you know most of the standard beats, the next step (I think) is to add your own variations, so practice turning a basic beat into something more....fancy, lol.