I have 128 cell trays and 50 cell trays that I start my seedlings in every year. I lay out the trays with a 11 by 17 inch sheet of paper, and write in what seeds I put in each cell.
Here's my too for this....dont put different types of plants in one tray. The cukes got tangled in the tomatoes and eggplant. It was hard to pot them up into bigger pots.
Some things I should have done differently:
Like I stated above, keep one type of plant to a tray. This is tricky for small gardens, because I don't need 50 tomato plants. Next year I'll start 50 and try to sell some at 1 or 2 dollars a piece.
Use larger cell trays when I don't need as many plants. That way I can leave them in the tray longer before I have to transplant to bigger pots.
More space. My growing space doubles as my woodworking space, and I really need to separate the two.
Thanks for looking.
Happy growing
Caveman