My advice would be, dont get too hung up on a route plan, just have a start and an end point, buy a map and just see where you end up.
I went to Toronto with no clear plan, I stayed in a hostel, met an Aussie bloke called Jambo, within a week, I was in Vegas, made my way up the West coast, then into Canada, up to banff, met some French girl in a hostel there and we travlled to Calagary, then I met some Aussie girls in Calagary who fancied whistler, so I travelled there... there I lived with some Japanese ppl for a while, then met a bloke there who was travelling to Kelowna, so went with him, picked apples there for a month.... and so on and so on....
My point is, youre gonna meet so many cool people along the way, who youre gonna hang out with, and want to travel with to other awesome places you'd never even heard of / considered, so my advice would be, have a start and end destination, it might even be worth applying for a working holiday visa for USA/Canada because I promise you, you wont wanna come home, so itd be sweet to have the option of staying and working for a year....
other than that, just go with the flow maaaan!
ps, when you have an accent, you can totally punch above your weight when it comes to American and Canadian girls! thats the best part about travelling to be honest, fit birds you'd neve have a chance with in England are more easily accessible! wooo!
PPS: if youre going to California, Id highly reccomend the Oregon coastline, its not really that much further and it's completely amazing!
A bit further up and you'll be in Canada... Yarrr!
Anyway have fun! if you end up in Vancouver send me a PM and we'll go for a pint!
They have Newcastle Bronwale on tap here y'know!

Hi Peace, Hi cabbage btw :)