Too amateurish - investment is like any other things, there is upside and there is downside. You want to risk more, then you may gain more (or lose more).

If you want reduce risk, you can buy more treasury notes and less stocks. Even stocks have risky ones and less risky ones. For example, Microsoft is far more stable than, for example, Plug-power. On the other hand, Plug-power increased 30% the other day, while Microsoft MAY not have changed much in the past few years.