In order to cast a spell, you need first drag its icon onto the hotbar located on the top left of your screen. What is more, it is in need to equip a staff. Get ready for your staff by pressing R. In the event your desired spell locates in slot position 1 you press the 1-key on your keyboard to get ready for your spell. If you see your spell selected as the active spell at the bottom of the hotbar, it means you are ready to cast the spell. Then you press and hold the left mouse bottoon to cast. Finally release your mouse button to fire your spell if it is in your sight.
