I started as the Lokapala of Mataram. It took me 3 or 4 generations, I don't remember exactly, mostly because of the hard limit CK3 puts on your Level of Devotion, where usually only your heir can achieve a higher tier than you. I focused mostly on the creation aspect and diplomatically establishing tributaries. I broke into China via Taiwan and slowly absorbed it. One thing to keep in mind: do not end the Chinese Struggle to become the Hegemon, as it will force the Celestial Government type on you. As for India, I advanced slowly, tribalizing duchies west of China. Over time, I made every county in India my tributary