The picture leaves the wiring diagram a bit less than clear.
Assuming you have a 110V coil on the relay, you connect power to the float switch, and then to one side of the coil. The other side of the coil connects to the neutral (other side of the power line, US-spec 110V).
One side of the coil is the terminal lowest and toward the front, as can be seen by looking at the wire. At a pure guess, the other is the other one nearest the table in the back.
Power for the motor is connected to one side of the switched contact (likely the terminal on back, second from the table). the motor is connected to one of the switched contacts (middle, top and next to top) and the neutral. You have a choice of normally open and normally closed (usually, and "I think, based on picture").
If you can manage a picture or scan that the diagram shows up in better, guesses could be better - or link to a page with a description of the relay.