Here are important considerations to keep in mind as you study:
Consistency is a better indicator of successful study than the number of hours in total you have spent. This is particularly true for subjects that require memorization. For example, let's say you have to memorize 49 vocabulary words in a week. Student A memorizes 7 words a day and reviews words from previous days. This takes the student 20 minutes a day. Student B crams all 49 words at once at the very last day. Although in total, both students may have spent an equal amount of time studying, the consistency that Student A will clearly be more effective for both long-term and short-term memory. You can think of memorization like painting a fence. The more layers you paint, the stronger the color. And if you leave time to let each layer dry before painting again, you can make the coating sturdier.
Develop a habit of studying, and don't rely on motivation. Motivation is temporary. A classical example is the New Year's weight loss resolution. Tons of people crowd gyms in January and February but gradually disappear with time. These people operated on motivation. Meanwhile, those who have develop a habit of working out go to the gym regardless of the time of year. You want to develop a routine of studying. Like how someone's day may not be complete without eating dinner or working out, your day shouldn't be complete until you have put in your 20-minutes of vocab review.
Don't forget the value of delayed gratification. It is so easy to become impatient and demand results in this day and age of technology. But, the harder you work for something and the longer it takes, the more rewarding it will be when you finally achieve your goal. College is a great example. Many people study and work hard to get into a good college so that later they will have a higher chance of finding a job with a competitive salary. The process of graduating from high school and college takes years. The benefits of making a decent amount of money, however, are significant. You can afford a car, a home, vacations, retirement plans, and more.
For specific strategies for memorization, problem sets, and essay writing, check out this video!