First, if you don't have Gmail keyboard shortcuts enabled, turn them on in Settings. You'll be glad you did. If you spend a lot of time in Gmail, you'll start shaving milliseconds of every action, which adds up. Get through a hundred or so messages every day and you'll end up with extra minutes each week to read your favorite blogs in Reader -- using Reader's keyboard shortcuts of course.
Here's how I read my mail:
1. Log in.
If I'm on my own computer I don't even have to do this, since I have the "Remember me on this computer" option checked on the Gmail homepage.
2. Get rid of stuff I obviously don't need to read.
I scan the senders and subjects of unread messages in my inbox, navigate through the messages using k to move the cursor (little black triangle) upwards and j to move it back down.
As I'm moving around, I select all of the messages I haven't already filtered but don't need to read using x.
And archive them all with y (e works for this too). Now I just have the messages I should read.
3. Get through the mail I do need to read.
I find a message that looks important or interesting, and open it using the enter key. If I need to reply, I hit r. Reply all? That's a. Once my response is ready to go, tab + enter sends it on its way. Back to my inbox with g + i. More navigating around with j and k, selecting with enter. Archiving (y) and replying (r). Starring some stuff for later (s). The occasional forward (f). Sending with tab + enter.
It may seem like a lot to remember, but for me, these eleven shortcuts have been invaluable and aside from j and k, which I just had to practice, pretty intuitive (g + i? that's for "goto inbox"). If you ever need a quick refresher, hit ? anytime to see the shortcut reference guide. And if you don't like any of them, you can edit the defaults and define your own by enabling Custom keyboard shortcuts in Labs.
Link - from Gmail Blog
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