Something that has been helping me a lot lately has been my garden journal/ foraging drawings. In my garden journal I write down when I plant when I fertilize and so on. That way when I wonder why my peppers aren't as tall as their neighbors I can refer to the journal and find out when I planted them and fertilized them and adjust accordingly. You can also use this as a reference the next year when you go to plant you will know when you can expect the plants to come up and bear and so forth. If I would have known this year that hot peppers can take three times as long to germinate as sweet peppers and five times as long as tomatoes I would have started them much earlier. On a side note did you know that a peppers scoville heat unit (peppers are rated by scoville heat units on how hot they are the higher the capsaicin the higher the shu) will help you determine how long it will take to germinate? The buht jolokia (ghost pepper) regarded by many as the hottest pepper can take up to 100 days to germinate! You can also use it to document what pests came to your garden at what time so next year you will know to spray your radishes by mid April if you want to keep the white flies at bay. It doesn't have to be long and flowery, it can just be something along the lines of " may21st planted 12 radish seeds directly into the garden and covered with loose mulch" that will be all you need to know. Or you can get long and poetic with it and leave it for future generations.
Writing down your foraging finds is another great journal. I keep my garden journal and foraging journal is the same book simply because I know that that book is probably going to get dirty! When I find a patch of something tasty I write down where it is and how to get to it including landmarks. Be careful choosing your landmarks that dead tree in the park may not be there next month or next year! I also like to sketch my edible plants, each part and each stage of its growth. write down any pertinent information to the plant, such as where it likes to grow, the easiest way to harvest it, the plants it usually grows beside, plants you have spotted that are similar and every difference you can find. Don't worry if you don't consider yourself a good artist, start with simple shapes and use a ruler or French curve to help you along the way. Remember you are the only one who has to see and understand this journal unless you plan to get all fancy with it to share with others. Use color descriptors or better yet color it in. If you really really can't draw you could take pictures and post these in your journal and write about your findings. If you are going to take it into the field try to pick a book with a hard back to make it easier to write in without a hard surface to lay it on. I will try to post some pictures of my field drawings and I would love to see yours!