This money is already income. Use your budget to determine where to allocate this income, and put it in an account appropriate to how you plan to use it. You're going to be investing for a long time before you have enough saved to withdraw more than $150/month and preserve the principal, and whether that's the best use of this money is dependent on the rest of your finances.

If you don't already have a budget: https://www.reddit.com/r/personalfinance/wiki/commontopics