Step 1: Take the huge pile of mail from the bin where it has been accumulating. Put it on the dining room table.
Two days later, Step 2: Separate out all the magazines and catalogs. Slice open all the envelopes.Organize by size. Make 4 or 5 neat piles on the dining table.
The following week, Step 3: Put the pile of magazines in the bottom of the mail bin, followed by the pile of catalogs, so that you have room to deal with the letters. Go through the letters. Set aside the envelopes, any mail that is junk, and any unneeded inserts that came along with important stuff. Recycle/discard/shred the detritus as appropriate.
The next day, Step 4: sort the mail into 4 piles: Very important actionable material; stuff that should be filed but doesn't require any action; things that require action but aren't time critical (like bank statements to be reconciled in Quicken); and everything else.
At some point in the future, but before the next time you have guests coming, Step 5: Put the mail into the bin on top of the magazines and catalogs. First the "everything else" mail, then, rotating 90 degrees so they wont get mixed up, the non-critical action material, then (again 90 degree turn) the filing, and finally (another 90 degrees) the important action mail. Put something like a place mat on top of the neatly sorted mail, then put all the mail that has arrived since you started the project on top of the mat (you don't want to mix up the old mail with the new mail.)
Congratulations. A job well done in only 5 steps.