formats may vary

book cover: 768 x 1200 (or anything proportional)

banner:1920 x 700 (my preference you can change the numbers)

icon: 500 x 500 (any square works)

wallpaper: 1242 x 2208 (or anything proportionate)

icon header: square or 1920 x 700 (not completely sure)

movie poster: 500 x 800 or 1500 x 2400 (anything proportional works)

bookmark: 200 x 800 (you're choice this is just my preference)

if you'd like any other dimensions comment below (: