My New Trades

So I was talking to another trader on the floor yesterday about pair trades. I know he does a lot of that and I've been pretty fascinated by the idea. I've been looking for some trade ideas to automate for a while. The thing with pair trade though is that what I was thinking about is the opposite of what Brian or conventional play which is to play for the divergence to converge back. I was thinking that certain days EWZ looks a lot stronger/weaker compared to SPY, but I was also just looking at the dollar amount whereas most pair traders look at percentages.

There's still a lot of homework I need to do on this. There are traders that base trades off of complicated algorithm. How do I find the pairs? How do I establish what's the norm for them and what would trigger the trade? Should I look at the change in dollar amount or percentage? Do I take a different amount of shares for the long/short? Should I trade in the direction of the divergence or trade for them to converge? If it's not working, how much room do I give it or willing to lose? If it's working for me, what's my exit strategy in that case as well?

So far I only have the LVS-MGM and SPWRA-SPWRB pair that I'm trying out. If you know any other pairs that's been working for you, let me know.