If you're new to marathon training, I have three tips that I've found to be really helpful in my own training.
1. Hydrate during your long runs. Not just before and after, during. I park my car with sports drinks inside it, where I'll pass by it once or twice in the middle of my run.
2. Incorporate training rest weeks. Not only are they important for a mental break, they also help your body recover and come back stronger than ever.
3. Ice baths are wonderful! Well, not wonderful, but sure do help. Take an ice bath at least after your long runs. I wrote a blog all about it, click here to read.
One more thing - don't forget that this is supposed to be fun! Marathon training is a big commitment, but it's also a fun challenge. Don't take it too seriously!