Shape of orbital is determined by quantum number:

Explanation

The azimuthal quantum number l fixes the subshell and therefore the shape, with l equal to 0 giving a spherical s orbital and l equal to 1 giving a dumb-bell shaped p orbital. The principal quantum number n sets the main energy level and size, m sets the orientation in space and s the direction of electron spin. Knowing which quantum number controls which property answers a whole family of questions.