I've been attended SDCC since 1985, which pretty much makes me an extremely experienced.
I've attended as gen-pop (general admission) from 85-95, exhibitor (working a booth) 1999-2012 & industry professional 1996-98/2013-now.
So, hopefully this will serve as my credentials & validate what I'm about to share here.
Personally, I don't bother wasting my time with trying to get into "the big rooms" (aka Hall H & Ballroom 20). The lines are ridiculously long - especially Hall H's! - and, since they don't clear out the rooms, the odds are stacked against you for gaining entrance (approximately 75-85% against getting into the rooms).
People literally camp out the night before just to get a chance to gain entry.
I'd rather spend my time either attending the panels in the other rooms or cruising the main Exhibit Hall, Artist Alley & Under the Sails.
As for seeing Cosplayers, there really is NOT a "best place," per se, since they're wandering about all over the place anyways.
Some of the booths in the Exhibit Hall do have "booth babes," but they've become fewer & far between.
Back in the 90's, there was free swag everywhere! However, ever since the recession, there's not much swag available any longer.
As far as off-site activities, they're mainly all thru-out the Gaslamp Quarter. For example, the Hard Rock is being converted into the infamous Belle Reve Prison (the super-prison from DC Comics' Suicide Squad). And, most of them are FREE.
OR...
There's also Zachary Levi's (TV's "Chuck", Disney's "Tangled") Nerd HQ, which will be at the Children's Museum. There's loads of interactive things to do - courtesy of Microsoft. The best part?
A lot of TV & Movie Stars tend to hang out here, mainly cuz they're friends with Mr. Levi.
I highly recommend against purchasing any food within the convention center. It's not very good and it's highly over priced.
Pretty much all of the eateries outside of Petco Park - home of the Padres - will be open, like the Tilted Kilt & Lolita's. However, keep in mind that pretty all of those places will be mega-crowded!
If you're only there to do star gazing (celebs), I mentioned Nerd HQ. Also, the Autogrpah Area is located Under the Sails. A handful of stars mainly from days gone by are there to meet, dign & sell you their wares.
However, if you're thinking that you'll be able to snag a "selfie" with a Kardashian, Matt Damon, George Clooney, Scarlett Johanson, Chris Hemsworth or any other A-Lister, you'd best forget about it. The lines for folks like them are almost as long as Hall H's! Besides, they also charge big money for photo op's.
OK, I know that this has been nothing but my being a buzzkill.
So, to strike a balance, here's some positive advice:
1. Get plenty of rest. You're going to need it.
2. Wear comfortable, practical shoes. You'll be on your feet A LOT.
3. Save your money & bring your own snackage. You might want to consider bringing a little extra, this way you could share & make some new friends while waiting.
4. Make sure your camera/phone is fully charged! You'll be taking a lot of cool photos. However, the Con does NOT provide charging stations!
5. Do your homework in advance! Make up a personal schedule of what you want to do & see.
For further info & tips, please check out these sites. You'll find them very helpful!
http://www.comic-con.org/cci
http://sdccblog.com/
One last thing:
If you're attending SDCC, please remember the following:
1. PLEASE - PLEASE - PLEASE ! BE AWARE OF YOUR SURROUNDING, ESPECIALLY WHEN IT COMES TO THOSE WHO ARE PHYSICALLY HANDICAPPED !!!!! DO NOT BE SO SELFISHLY FOCUSED ON EITHER GETTING THAT FREE SWAG OR GETTING INTO YOUR PANEL THAT YOU EITHER PUSH, SHOVE OR EVEN STEP ON/OVER A PERSON WHO'S HANDICAPPED, ESPECIALLY IF THEY'RE IN A WHEELCHAIR!!!!!
A couple of years back, the WB (TV network) Booth would distribute their highly-coveted "Big-@$$ Swag Bags" briefly during random times of the day. People got so focused & crazed about snagging their free bag that they'd do ANYTHING to gain an advantage!
Some people would step on & climb onto people in wheelchairs!
This was the ONLY time I've ever nearly got into a MASSIVE BRAWL with these EFFING IDIOTS!
As this little girl in a wheelchair was crying & screaming for this 275 lbs. jerkwad to get off her, I took action by grabbing his legs and yanked him off that girl! Once he got off the floor, he turned at me with his fat fist raised towards me. I took my (kempo karate) defensive stance, ready to rumble! He tried to take a swing at me, but then I pointed at the little girl he seriously injured. He dropped his fist and tried to walk away. Fortunately, security arrived, escorted him out and took away his pass.
So, please! Heed this request!
I'm sorry for "SHOUTING" this part, but I feel VERY STRONGLY about this! This is because my late father was a disabled military veteran.
2. Please be patient & polite! You're not the only person who's trying to get stuff done there!
3. Most Importantly, PLEASE HAVE FUN! Don't get so focused on obtaining swag or star gazing that you forget to enjoy what the Con has to offer!
I hope y'all find this very helpful.
I apologize for the length of this post. I just wanted to share from my 31 years of experience & be as thorough as possible
Gosh, all of the personal tips were truly insightful, however,
I'll add my final ten cents;
To "deal with the madness & chaos"?
I'd say, a visit to me in the midst of all of the illuminati and excitement,
shall suffice, by taking a short stroll to the Upscale East Village of The Gaslamp District;
literally steps away from all the mainstream action of the events. (3 minutes max walking time)
You will definitely experience "Celebrity Sightings". And Cosplay gals shall abound
enroute, and maybe even at your "final destination" 
Enjoy a relaxing, rendezvous of Certified Massage Therapy.
Perhaps a light lunch/dinner, a sip of fine wine with yours truly at an amazing,
"properly priced" bistro and finally, a delectable elixir of Muah!
"Just Call Me Super Woman" when we "Cosplay".
Angelina Jones
