I got a community garden plot and am struggling on where to start with my plan.

I got a plot at my community garden and I am super excited! I have thought about getting one for a few years but never actually did it. I used to garden when I was a kid with my parents but other than that little knowledge I'm a complete beginner. My plot is 10x15 and I'm at a loss with what to do with it! One of my friends recommended the square foot gardening book and I'm interested in that. The only problem is that I can only have a 10x15 raised garden bed per the garden rules. I don't think I can divide the plot into smaller raised beds. Is 10x15 too large of a plot to successfully do square-foot gardening in?

That issue aside, I am overwhelmed and have no idea where to start with planning my garden layout. I have a rough idea of what I want to grow but am struggling with where I should place plants in relation to each other as well as where to face them in the garden. I'm in zone 5, and garden access begins on April 15th so I have plenty of time to figure this out. Any advice you have would be greatly appreciated!