Rotation trouble (613862)

So i have an object that I have and its very rotated like a diamond and I want it to loop in a Update Loop to +1 rotation to the left so it spins. Problem is its already rotated,so I dont know how much of each axis I should rotate. Is there some math to know, And just in the future, to go left or right without looking at current rotation.?

Hope you understand and please make it simple. TY :slight_smile:

GUys Its been a day.