This game is relativly easy on Badass difficulty and shouldnt give you too much trouble.
Here are several tips to help things go a little more smoothly.
1.COOP: get 3 friends or join a multiplayer game, playing in 4player coop campaign makes this difficulty a breeze. If your downed your team mates can revive you.
2.SPACING: watch your spacing between team mates, if your all grouped together 1 stray grenade can see you starting from the checkpoint very quickly. Having said that tho dont put too big a gap between you otherwise if your downed you prob wont get revived.
3.TEAMWORK: Work as a team and communicate, If everybody does their best you will fly through the campaign, unfortunatly if you join random game there do seem to be the odd person who joins then goes to the toilet or something so you guys do all the hard work and they get to rest up.
4.FRIENDLY FIRE: Be carefull as on badass you can kill your own team so if your being swamped by aliens your just as likely to kill your buddy aswell as the xeno.
Flame throwers are the worst hazard for this so if your gonna grab one make sure you stay at the front of the team.
5.FRIENDLY FIRE 2: This is the good side of the friendly fire scenario, just been into battle, team member pretty low on health, if all is quiet kill your buddy and revive him, he will get back up with FULL health. Obviously not to be done in middle of battle tho lol
6.SLOW AND STEADY: Take each part slow and steady, dont rush into battle or you and your team will die very quickly.
7.RAVEN: While one or 2 of you take on the raven the other 2 kill all the xenos and assist with the raven when possible.
8.CRUSHER: All 4 team mates should keep a sensible distance apart and keep circling the crusher and firing at its back, keep an eye out for xenos.
9.QUEEN: The last level is really easy and easily done on your own but if your a 4man team then 1/2 keep the queen busy while the others complete the objective.
Hope these tips can help and enjoy the game.