Use 'S' to toggle snaps. In the Main Toolbar there is a Button with a Magnet, where you can toggle Snaps (similar to pressing 'S'), chose between 2D, 2.5D and 3D Snap (I only use 3D) and, if you rightclick it, you open a new window where you can choose what to snap and, for example, to use the Gizmo's Axis Constraint when…