You can watch the video below, but here are some of the Settings Matt Cutts uses for his Gmail account. The video explains WHY he chooses those settings.
1. Conversations per page - 25
2. Keyboard Shortcuts - turn it ON - Matt loves this one
3. Vacation message can be set so only your contacts will get the message (not a spammer)
4. Browser connection - he has it set to "always use https://"
LABELS - It's good to learn about this function. Very powerful. Now you can drag and drop.
FILTERS - you can have all mail from certain sources immediately placed into labeled folders
WEB CLIPS - Matt disables them (too distracting and not needed for him)
LABS - there is a ton of stuff in here, take a look, it is all disabled by default
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