I'm more than somewhat in to accents, my missus is a Yank. It's much easier for someone with an Estuary accent to emulate one of the East Coast accents than it is the West Coast.

On the West Coast they're incredibly particular about sounding out each syllable. Estuary accents are much more slack and frequently drop syllables and tend to speak quickly, all of the East Coast does this.

Not so much in California, but further up the coast in the PNW you'll notice they emphasise the 't' in words, it can be heard in Californian accents but isn't quite so pronounced (the missus was born in Cali, later transplanted north to Washington).

Given you're in Cali, it's probably better to aim elsewhere anyway, your mannerisms will give you away as a non-native recent transplant.

Perfecting an East Coast accent is a lot about being slack with 'r' (car - cahh, horrible - harribul) and the typical example of dropping syllables can be seen more famously in things like water - wuddah and shore - shaw. It's quite nasally and breathless. Contrast that with West Coast accents, especially in the PNW where water has a very pronounced 't' and feels as though it takes twice as long to say.

Another feature of the "typical" relentlessly East Coast accent and mannerism is seemingly not needing the initial syllable of a lot of greetings 'hey' - 'ay', 'hello' - 'ellloh' the 'l' is longer than your typical Estuary 'ello though and the end -o has slightly more of a rounded emphasis to it.