Setting up and rerolling the fast way:

1) Open a Google Chrome window in Incognito mode
2) Ctrl+Shift+I to enter Developer mode
3) On the Developer mode side toolbar there is a button shaped like a smartphone screen in the top left, click that so it's blue
4) Under "Device" on the orange portion of the toolbar above the webpage, select any model, I used Google Nexus 5
5) Visit http://gbf.game.mbga.jp/ on this window, you will be taken to a login screen with several buttons below it
6) If it's not visible, scroll down to the bottom of that page and you will see a gray button, click that one
7) You will be on a registration page where you have to enter an email, use a salted email (like [email protected]) and press the button next to it to be sent a verification email
8) Check the email you salted, you will get a 4-digit verification email you need to register on the page you entered your email on in the previous step
9) This takes you to a typical account registration page, the nickname you give yourself will be the default name Granblue fills in for you when you start the game
10) If the registration is successful, you will be taken to another page with an orange button that launches Granblue
11) Click the game start button and when it pops up with all the graphic and sound settings, click the bottom button on both pages to minimize all of the game settings, they can be turned back on and even improved later
12) On the third page you will see your account's username, click that button if you want to change it, then click the button below it to start the game

13) When the tutorial actually starts, you will notice in your URL bar an address ending in "#tutorial/3". To skip through the entire tutorial, you can increment the number at the end of the URL bar by 1 over and over to skip to the next step until you reach the end of the tutorial. However, there are a few numbers that are skipped and throw you a page error if you attempt to visit them directly, the numbers being 13, 21, and 22. If you hit one of these error pages just go back a page and enter the next correct number. You will basically be going from 3 to 32 by 1, skipping those three numbers, and when you reach 32 you will be taken back to your account's "My Page" screen.

14) From the My Page screen, click the arrow on the right side of the screen to visit "Town" area and click each gold sparkle on the map to get some items. After you get all 4 items, visit the sparkles again from top, left, right, to middle. This will give you an extra Legend Gacha ticket so you will be able to do 2 rolls per account reroll.

15) Click the Menu button in the top right, click プレゼント on the right side of the "Item" set of buttons, and click the blue button next to the Legend Gacha ticket you just obtained in the previous step to redeem it.
16) Click the Menu button again, click ガチャ fourth from the left at the top to get to the Gacha screen
17) Scroll down past the scrolling banner, gacha information, and 10x roll boxes, and you will see a 1x roll box. The second blue button on this window is to roll using free tickets, so roll both now.
18) If you don't get a character you want, just close the Incognito window and open a new one to start over, this saves you from having to clear cookies and everything else to start over. If you DO get a character you want, just remember the salt you used to create the account and log back into the game outside of an Incognito window and start playing.

While this is a lot of steps, once you get through it once and understand what needs to be done, the entire process will take less than 5 minutes per account.