First off, answering a few more nuts and bolts logistics questions that are popping up a lot in the Google searches:
Yes, most of the autographs cost money above and beyond your admission ticket. Unless prices have gone up this year, expect to pay $5 for Corner 1, $10 for Corner 2, $15 for Corners 3 and 4, And anywhere between $20 and $50 (for bats and jerseys) in the Legends/HOF Corners 5 and 6. Corner 7, aka "Down on the Farm" is free. The price is per autograph session, not per player. EDIT---NOTE: The prices have indeed gone up. Sounds like $5 more per corner. Prepare accordingly.
No, I do not know why they call them "Autograph Corners" when most of them are not, in fact, IN corners. Personally, I think we should call them "Autograph Nooks." It's cozier.
The photo area is
Gates F and H should be open, and Will Call tickets should be available at either gate. Doors open at 4pm on Friday and 9am Saturday and Sunday. Lines will form well in advance of the doors opening.
The lines for Mauer and Morneau will be long. LOOOOONNNNNNGGG, I tell you. And you can try to tell yourself that since it is so freaking cold out, no one will be in line very early. But you would be wrong. I have found that it's a good rule of thumb to just assume that in any given situation, there are at least a few hundred people who are crazier than you are. Plan accordingly.
The food options at Twinsfest are a scaled down version of what was available during games at the Metrodome. Dome dogs, hamburgers, chicken sandwiches, nachos, etc. (And beer!) Last year I ate the worst mini donuts in the universe, which were cooked in what looked like a toaster oven. They came out charred on the outside, frozen solid in the middle. And I got a weird rash from the Maui Waui smoothies. (I blame a previously undiagnosed allergy to "Waui.") So choose wisely.
There's no map of the layout online unless someone somewhere has scanned one from previous years in themselves. I looked to see if I still had one from last year, but I don't. But entering in through either gate will get you where you need to be.
And now...onto my own personal ideas of things people should know.
What to carry with you:
Cash--Some individual merchants at Twinsfest may have credit card machines, but a lot of stuff is cash-only, including the autograph lines.
Hand sanitizer--I cannot stress this enough. Every year Twinsfest breeds the flu bug like nobody's business. I also recommend slamming some Airborne before you go to keep your immune system in tip top condition, because it is going to be working overtime.
Whatever objects you'd like autographed.
Asprin/Your headache reliever of choice--Maybe it's just me...but I find painkillers to be a godsend every year at Twinsfest.
Something to keep yourself occupied in the mind-numbingly long lines.
Your best manners.--Don't be a dick, please. Being polite and friendly to the players and your fellow 'Fest attendees makes everything go so much better. We're all in this together!
Things you DON'T need to carry with you:
Pens, Sharpies, whatever other writing implements you might usually need for autograph-seeking--The tables come fully stocked with pens and sharpies in different colors...black, blue, silver, and gold. No need to bring your own. Most players are pretty accommodating about signing with whatever pen or marker you want, but if you have a strong preference you need to speak up and ask, otherwise they will probably sign with whichever color they have in hand.
If you find yourself in an autograph line, and you don't know who one (or any) of the players actually are, ask the person standing in FRONT of you, if you must. Because if you ask the person behind you, they may be the tiniest bit resentful that you are making their wait longer. Especially if the person behind you is me. I only mention it because it happens to me every year. If you feel like you MUST ask the person waiting patiently behind you, and they answer you...I think you should then offer to let them go ahead of you. Just my opinion.
Sometimes you can get through the $5 and $10 lines (and sometimes the Legends/HOF lines too) faster if you wait until the tail end of the scheduled autograph time. Because at the end, most of the people in line are waiting for the next group of players, and you can frequently skip right to the front. Of course, that's a gamble, and I don't recommend trying it for lines that are outrageously long to begin with.
If you do not make it through an autograph line before the cut-off, you have the option of staying in line for the next player(s). So if you know ahead of time that you're going to be in a high-risk line (ie Mauer/Morneau), you might want to plan ahead and decide if you'd be willing to get the autograph of the player following them instead, and pack something for that player to sign too.
The photo line has volunteers snap a picture of you with your favorite players, using your own camera. So don't forget to bring the camera/batteries/SD card/etc. I actually sometimes pack an emergency backup camera. Which sounds ridiculous, except that it came in handy last year, when the battery popped out of my first-string camera and I lost it.
Don't miss the minor league displays. All of the teams in the Twins' farm system are represented, and you can find a lot of really cool merchandise you can't find anywhere else. This is a good place to look for items for the prospects to sign, as well as finding some unique items featuring current Twins in their younger days.
If you really are committed to getting a lot of autographs, it's good to plan out your schedule and prioritize ahead of time. There have been years where I'm not ashamed to admit to using an Excel spreadsheet color-coded for prioritizing.
Of course you should also be flexible enough to call an audible when you need to (sorry for mixing sports metaphors). If a certain line looks longer than you anticipated, or the dreaded flu strikes your favorite player, there are always a ton of entertaining things going on you can try. Last year, Joe Mauer filled in at the photo line last minute, and Carlos Gomez went salsa dancing in the Celebrate Diversity area. Something wacky can always happen, and you don't want to miss it because you were a slave to the schedule.