The biggest issue unsuccessful new hires have involves attitude.
If you show up prepared, act professional, put in the work, mentor others, ask others to mentor you, forget what you did at your last company, work hard, and study, you will do fine. Even if you are slow to grasp some things, the company will be more willing to work with you with tutoring, extra sims, etc if you have a good attitude.
You'd be shocked how many show up to class with attitudes like:
* well at my last airline we did it this way..or
* this is a stepping stone to the majors so I'm only here temporarily..or
* dude we're airline pilots now let's blow off studying and just go to the bar...or
* I want to post pics of my ground school books on instagram rather than pay attention...or
* I don't need to study because I have the gouge...or
* My dad is a Delta Captain so my ticket is punched...or
* hey let's spend our sim times doing selfies or go-pro-ing .
You get the idea. Be humble and listen. You're there to learn.
Your walls in your hotel room should be plastered with cockpit posters (of the plane you're actually flying), notecards, limits, etc..
You should have a stack of flashcards in the bathroom for reading. Also on your nightstand to read before bed.
Download Quizlet and make electronic flashcards that you can use over all your devices.
Stuff like that is what will make training less stressful for you.
You get the idea.