Using standard colloidal silver generators the technique is pretty simple. The key ingredient is the use of distilled or very pure water.
The purer the water the better the finished product. NEVER add anything to the water.
When making Colloidal Silver let your generator run until you notice a yellow tint to the water. Once you notice the yellow color, stop immediately. Next time you make CS using the same quality and amount of water, simply stop the procedure about 5 minutes or so sooner.
If you still get a yellow color with the finished product0 stop 5 minutes earlier the next time. Keep doing this until the finished product is a clear to only a very light, pale yellow color after it has set overnight.
The idea is to stop right before you start getting the yellow tint. The yellow color happens normally around 8ppm - 9ppm. When you stop a bit short of that you should have the 5ppm - 7ppm that most researchers say is the desired ppm.
If you get any cloudiness or a milky-look, a dark tint or color, your water is probably not pure enough. Throw it away (or water your plants with it) and start over.