First, be sure the gun is unloaded and the magazine removed.
Pull the slide back until the larger cutout in the lower edge of the slide corresponds with the round part of the slide stop lever (it goes through the barrel cam and holds the gun together, essentially.) Once the cutout in the slide lines up with the slide stop lever properly, you can push the slide stop out from right to left (it might be a little tight at first). Then you can pull the slide and barrel forward off the frame. Remove the recoil spring on its guide rod carefully from the barrel by compressing it slightly, but be careful so you don't launch the recoil spring across the room. That's all the disassembly you need to properly clean the pistol.
Reassembly goes in reverse order: put the guide rod with recoil spring back under the barrel, and push the entire assembly back onto the gun from the front of the frame. Once the slide is back on, you can insert the slide stop in its hole and exert light pressure on it as you move the slide back slightly...when the slide and barrel have reached the right position, the slide stop lever will snap back into place.
If you want written instuctions, go to the Smith & Wesson web site at www.smith-wesson.com, and fill out their online request form for a manual. They will send it to you within a week free of charge.
