Search for companies with a minimum purchase requirements low. Some businesses will allow investors to start it with small deposits, but you’ll have to agree to automatic investment plan whereby you give them to deduct a fixed amount from your bank account you each month for the purchase of additional shares that is best way to invest cash such amounts can at least $ 25. You may also be required to start with a small one time investment, sometimes as low as $ 25. As I said, this is an easy and relatively cheap to build a portfolio of securities. Put into an index fund tracking the broad market. Through years of boom and economic decline, the index mutual fund, tracking the S & P 500 index has returned around 10% per year. It was a very good comeback with your US dollar, and has a lot of money does not just not do much for their customers. There are many other indicators that you may choose to track that could bring greater profits. Once you choose an index fund and your first contribution, you can add many dollars as you want as often as is convenient, without any cost or commission. You can also stop participating freely whenever you want. Work directly with a company in this way, you do not pay any commission.