Here is some readerly/teacherly advice on the summer reading. Take small bites. Like eating, reading too much in one sitting can make you sick. If you make a goal to read 50 pages and can only process (grasp, understand) around 30 pages, but press on because you are short of your goal, chances are pretty good that you'll have to go back and re-read the 20 pages your eyes merely glanced over. It's frustrating to read things twice, but sometimes it is necessary.
Now, I realize that the reading you have before you is somewhat time sensitive (read as: there's a due date) and that you are either working, playing a sport, helping out around the house - or all of the above - taking all of this into consideration, you have to make reading a priority. Put it on your to-do list. MUST READ THREE CHAPTERS OF CATCH or P&P. Take small bites. Read only what you will be able to process and annotate without your eyes going crossed. Don't get frustrated if you can only get through two chapters instead of three. Some chapters are meatier than others and involve more chewing.
Some don'ts: Don't read late at night - you will fall asleep. Don't try to read when there are a lot of distractions, especially if you are easily distracted. You won't pay attention to the reading and will be forced to re-read. Don't read outside in a thunderstorm. The book will get wet.
Some more advice: Bring the book with you wherever you go. You never know when you'll be waiting - in traffic, in a restaurant, at the doctor's office, in line at the store - and waiting time is reading time. Stephen King offers this advice in his book On Writing and I have been bringing a book with me wherever I go ever since. Make the most of your time. Read, don't wait.
Does anyone else have advice on how to make the reading easier/more manageable?