Provide advice on how to accomplish the following goal. Give ONLY the advice, no other words or explanation.
For example:

Answer: <advice, as short as possible; a single sentence!>.

Goal: How to Make a Sponge Motorboat
To make a Sponge Motorboat, first build a propellor by cutting off a slice of cork from a wine bottle and push it on your motor spindle. Make sure it can spin freely.
Soak a sponge in water, attach a motor to it, and secure a propeller.