This is an excellent question, and I'm sure everyone has different methods of concentrating, however it's important to figure out what works for you. For me, I like to keep it simple:
- Organization is key. Before going to bed at night, I make sure that my next day is scheduled out.
- Make a to-do list every day, and try to tackle the most difficult things first.
- Eliminate distractions and time wasters. I like to disable push notifications on my phone, so I'm not tempted to take frequent breaks to check text messages, emails, social media while I'm working.
- Regenerate and keep up your energy. For every 1 hour that I work, I like to give myself a 5 minute break to stretch, walk around, get some water or food, or socialize with peers. This keeps my mood positive and helps me not to get overwhelmed.
- Constantly remind yourself of your ultimate goals. I keep them written on a post it on my computer. If I ever start to get frustrated, it helps to remind myself what I'm working so hard for. Keeping your long term goals in mine while accomplishing day to day tasks can help you stay motivated.
- Exercise/meditation. Moderate and regular physical exercise before taking a test can increase your attention span, discipline, and memory retention. It also will help to boost your overall mood and mindfulness.