If a guide rail is included, make sure you use it correctly so that you do not saw into it. Check with the owner how to use this particular guide rail.
Only saw in wood and make sure that there are no nails, screws or other hard objects in what you are sawing.
Check with the owner which blade is included. If you are going to cut a lot, a coarse-toothed blade is preferable, while if you are going to make fine cuts, a fine-toothed blade might be your desired choice. However, a fine-toothed blade can wear out unnecessarily if you use it for mass cutting, so make sure it is the right blade for the job you are going to do.
Do not apply pressure but let the saw work its way through the material. If you apply too much pressure, the blade can become too hot and the resistance can become too much so that the motor breaks.