Your altar is where you’ll be focusing your energies for rituals, ceremonies and magickal works. Some things to consider: where your space will be located, how large it will be, will it be a permanent or portable altar, what tools you’ll need and what type of ritual or work you’ll be performing.
An altar can be a permanent table in a special room, or a folding table that gets put away after each use. If you have an outdoor space, a tree stump or just a patch of ground may serve as your altar. You’ll need less space for rituals involving one or two people than you’d need for a group. Keep in mind, a pagans place of worship or sacred space, is wherever the pagan is located. You don’t need to go to a specific, fixed location to practice your beliefs. Nor do you need all the tools and objects. As I've said before, all those things are just the trappings that allow you to focus. They're great to have, but not having them does not mean you can't practice your beliefs. In fact, I once read a very beautiful story of a woman who was bedridden and unable to participate in a sabbat ritual. Instead of missing out, she chose to hold the ritual by visualizing the scene and the ritual step by step. For her, it was just as fulfilling as taking part physically. Never underestimate your mind, it's where it all takes place!
This is an example of an ingenious portable altar kit that is commercially available. The box can store all you need for your rites, and will also serve as the altar itself!
A beautiful example of a more permanent style altar set up in a home.
A tree stump makes a nice altar setting.
A permanent outdoor space large enough to hold a ritual with several people.
As for the layout, it should be arranged and designed as fits your wants and needs and the ritual/working being done.
Some divide the altar by feminine and masculine: