The Sealer does not use an ON/OFF switch. Power is only used when the sealer arm is fully depressed and the seal light illuminates. Plug in the power cord and set the timer dial to the "2" position. Place a plastic bag or piece of tubing over the teflon cloth sealing surface and push down on the handle of the arm completely. Firmly hold the arm down through the complete sealing cycle. (The sealing cycle means that the read sealing indicator light will illuminate, then quickly turn-ff). After the red sealing indicator light goes off, continue to hold the arm down for another second or two. This allows the seal to cool, and strengthen under pressure before you raise the arm and check the seal. Check your seal and if necessary, SLIGHTLY increase or decrease the setting on the sealing timer dial, then try this procedure again until a strong seal is achieved. For the strongest seals, keep experimenting until you find the lowest setting on the sealing timer dial that still makes good seals. Thicker material requires more time to seal then thinner materials. Should plastic stick to the white silicone rubber strip in the arm or to the Teflon cloth covering the heating element wire, hold the arm down a little longer at the end of each sealing cycle. Clean off any plastic residue with a DRY cloth, never use water to clean.