The direction of an electric field at any point is the direction that a
small positive charge would want to move if it were located there.
We know that like charges repel. So the electric field around a
positive charge always points away from it.
The electric field at a point to the left of the positive charge Q
points away from Q, toward the left. A small positive charge
located there would want to get farther away from Q, and it
would try to move farther left.