Think of the altar as an extension of yourself. It's left is the same add your left. you can put anything at any spot you want on the alter. Although there are some things that correspond with the different elements, and directions that correspond with the elements, i don't actually think it matters if they are in the same directions. The pictures of altars that are in books and on websites are just guidelines. You can alter your altar to fit whatever is comfortable for you. Also it's okay for you to have an electronic book of shadows, don't worry too much about putting it on your altar. You would only need that if, say you need to follow instructions. But some say that metals can funk up spells, so i don't know about putting the flash drive on your altar. If you really need it you could print or write down the part you needed for the working.
The craft is flexible. There aren't really specific rules you have to follow