Great question to post. I think you basically want to jump year round and are looking for the best way to go about it.. (Y/N?) Let me try to break it down into several parts.
Nutrition- Each person is very different and will have different needs. A high school female, depending on her size and average daily activity will burn less calories per day then a 25 year old man doing the same activities. I don't know how much you weigh, your height, or what you do in your daily activity but you can look up a basic calorie calculator on Google to determine how much you will need on average. It is important to make sure that you get a proper ratio of carbohydrates:protein. My girlfriend pretty much tells me what to eat but I think she is always rambling in my ear about 5:1 ratio. That could be off though, I will gain more information for you. Also staying hydrated is key to proper nutrition. Most people consume up to 30% of their daily calorie intake in what they drink. If you need an average of 2000 calories per day and have a glass of soda for lunch and dinner, you just drank about 300 calories and didn't even realize it. That adds of very fast. The best way to go about nutrition and the thing I tell my athletes is this: If it has an expiration date that is more then a few weeks away, you probably want to stay away from it. Most things that are healthy for you do not have a great shelf life for example, fruits, vegetables, fresh cut meats, yogurt and other milk products, and whole wheat bread. These things you don't want to eat if they have been sitting around for several weeks. Stick to the old school food pyramid and you will be fine. You don't have to eat 5-8 times a day if you are eating healthy well balanced meals, and honestly how many people can stop what they are doing to eat that many times in a day?
Training- Difficult to say what drills you should be doing before any meet. I am not familiar with your training schedule, the way you jump, or what your weak points are. I know for my athletes I try to break down what they are doing best to worst. If I have a kid who has a great take-off, but his/her swing is terrible, we will work rope drills and short approaches until he/she is consistent and I like what I am seeing.

The way you can help yourself is list the main parts of the jump. Run, Plant, Jump/Take-off, Swing, Turn, and Top-End. Put them in order of best to worst. Whatever the worst part of your jump is, that's what you should work on. The day before MOST meets is strictly for measuring steps and active rest, warm-up, active and static stretching.
Rest- Each phase of each year is different and each athlete is different. Summer is the time to get in as much work as possible for two reasons, kids have the time, and if they get hurt, they have plenty of time to get healthy again. That being said, you must be smart with your rest at any point in the year. If you do have a coach, he/she should tell you to take certain days off. Often I will let my athletes go home the day after big meets. Summer time we will lift and do a lot of speed and strength training and each day is set up so that my athletes are not over-training. They may lift one day, then do speed training the next and have a full day off or do easy drills to keep them fresh. When summer is over, rest goes up but work load changes as well. We will run more in the fall and lift less. This is so that I do not have to spend all my time and energy fixing runs come indoor season.

The more sleep you can get the better. 9 hours would be awesome but you will be lucky to get 7. Try to go to bed at 10pm that way you can get a good 7-8 hrs in.
What My Schedule is....
I won't go into specifics considering it will take me way longer then I wanted (and I already spent too much time on this) but I'll give you a quick breakdown of what we do...
Summer Training
Mon/Fri- Lift Legs/ Core Workout
Tues/Thurs- Lift Upper (Gymnastics if you can) Speed Training
Wed- Technique Day (Very Light, Low Impact)/ Core Workout
Sat/Sun- One day will be rest, one day will be a jump day. Don't over jump yourself.
Fall
Mon- Lift Uppers
Tues-Speed Training/ Technique
Wed-Rest
Thurs-Speed Training/ Technique
Fri-Lift Lowers
Sat- Rest
Sun- Jump Day
Winter- Lifting will be every day, but usually in gym class or sometimes after practice. Never hard, usually 3x10 only to maintain strength not to make tired. You want to lift only what you can handle. I will show what we would do if there was a meet on Saturday.
Mon- Speed Training/ Short Jumps/ AM Lifting
Tues- Ground Technique/ Rope Drills/ AM Lifting
Wed-Jump Day (As many as you can get in) No Lifting
Thurs- Short Jump Day- No Lifting
Fri- Warm-Up, Stretch, Rest
Sat- Meet
Sun- Rest
Spring will be similar to Winter, however I will stop lifting totally at some point in time, depending on when I want my athletes to peak. Hope this was helpful for you, and I am sure there will be a lot of people who will tell you to do something different. This is what I have been doing for several years now and my athletes get good results from it, so I feel that's all I can ask for.