Start Early. If you know you need to be at weight on a particular day, plan to be at weight 1 month ahead of time. Also, everyone's body has "sticky points." For example, every year it would take me a month to go from 130.8 lb to 129.8 lb. I knew this because I did it over and over again, and every year this would predictably happen as I approached 130lb, the lightweight women's maximum for most collegiate and national level races. Everyone's body is different, so make sure that you know how your body responds and leave time for surprises. Nothing saps your strength like trying to lose weight too quickly.
Fuel Your Training. We are athletes. The goal of training is to get stronger and faster, not to lose weight. Don't sacrifice your training. Eat to fuel your workout and focus on losing weight for the rest of the day. This is the concept behind energy neutral training. If you fuel your workouts properly, you will recovery more quickly and be less hungry for the rest of the day. Make sure that you're eating enough during your workouts. This takes personal experimentation: the moment your gatorade tastes like "liquid courage" or it becomes a drudgery to turn your pedals, you know that you are in the hole and should have had more snacks sooner in your workout. Follow up your workout with a recovery snack with a carbs to protein ratio of 4:1 within 20 minutes. A smoothie is a great way to get this nutrition as liquid is easier to digest.
Proper Nutrition: enough protein, iron, ect. I perform poorly if I don't get enough carbs, but many of my lightweight teammates could get away with fewer carbs but would perform poorly if they didn't get enough protein. Everyone's different. By carefully choosing nutrient dense foods, it's possible to meet your rebuilding requirements in macronutrients while still running a (slight) caloric deficit. This takes a lot of planning, but the Thrive diet has some good ideas to this end.
I'll confess... team USA lightweights did sometimes eat frozen yogurt for dinner. That's right, we replaced our lean protein & veggies with frozen yogurt. Sometimes this just had to happen to break up the monotony when there just aren't enough calories in the day for months on end. But don't make it a regular occurrence. And seriously, if you're going to be allowed to race even if you aren't at racing weight, eat your dinner first. Poor nutrition leads to underperformance and injury.
Sleep. Go to bed early and get enough sleep. Extra sleep will help you recover, and your recovery will need help if your body isn't getting all the nutrients it needs (see "proper nutrition"). Often times, we mistake tiredness for hungriness in the evenings and if you're sleeping, you can't be eating. Plus, no one likes it when you're hangry. Just go to bed so you still have friends when you wake up in the morning.
Water, Air, & Fiber. These should become your 3 new favorite food groups. Drink water, herbal tea, eat soups. Contrary to intuition, making sure you're hydrated will make you retain less water. It will also make you feel fuller; there's only so much room in your stomach. High fiber foods are great too, especially because high fiber foods like vegetables tend to be nutrient dense. Consider the nutritional profile of cauli-rice (recipe here. Did you notice that cauliflower is a complete protein?) versus brown rice and spaghetti squash versus whole wheat pasta. You're getting a lot more micronutrients and bang for your buck in terms of proper nutrition. Air is a fun one, and no, I'm not talking about the chocolate bars with air in them. I was thinking more of popcorn, which is my favorite snack ever. My current recommendation: buy a popcorn popper and some kernels then top it with siraccha. Trust me, this is awesome.
Salt: Be careful about limiting salt, but if you retain water at that time of the month and you need to weigh-in, making sure you're only getting 100- 150% of the "recommended daily value" can mitigate that.
MyPlate. Livestrong's MyPlate is wonderful. I've been a member on this site probably since it started and it made dropping weight so much easier. It's even great to just monitor what you're eating to make sure you're eating a balanced diet and getting enough of key nutrients. Two tips: 1) make sure that you put your activity level as "sedentary" or "lightly active" if you're going to add in your training separately to the activities section. 2) Make sure that it's telling you to eat enough. I started to notice that it was underestimating my caloric needs as I got into my later 20's. I guess it's because most regular people are softer at 29 than when they were in college, but most athletes are actually leaner, which means their basal caloric need is higher. So use your judgement, but either way 1500 calories is NOT enough to fuel serious training.
Try Vegan. A whole food plant based diet tends to be very nutrient dense. Vegan foods also tend to be heavy hitters in the big three mentioned above: air, water, and fiber. If vegan is a big change for you though, be sure that you're getting enough iron and B12: deficits of either of these nutrients, which can happen even in a well-balanced vegan diet, can severely derail your training. Another option is just to swap out one of your favorite staple foods. When I was rowing and it was time to make weight, I would always cut out peanut butter!