How to be a millionaire by forty

I'm 23 (and a half) and I took a look at some arithmetic and found that with thrift, becoming a millionaire just isn't that hard. Over the course of this blog I'm going outline exactly how I make a million dollars. I will keep as much detail as possible in my attempts to make money. Insomuch as I can maintain my privacy (and make sure none of my ideas get scooped) I'll explain my business ventures, budget, investments, and savings plan.

I'll begin by explaining my current budget and savings plan.
I make about $32000 per year, after taxes and contributions for my health, dental, and life insurances I take home $1890 per month.
I use www.mint.com to track my budget and a typical month amounts to:

Rent: $350
Food: $550
Vacations: $100
Electronics and software: $100
Investment: $300
Cell phone: $100
Utilities and internet/tv bills: $45
Cell Phone: $100
Gas: $125
Gifts: $50
Home Upkeep (supplies, improvement and furnishing): $50
Books: $20

Most of my discretionary income is taken up in food. In order to become a millionaire by 40 in 15 years I need to invest $3,600 a month every month until I’m 40 assuming an 8% rate of return. In order to accomplish this, frankly I need to make more money. If we can get the rate of return up to 12% then I can reduce the monthly investment to about $2,800. At my current monthly investment it’ll take me a 40% rate of return on my investment. I don’t think its realistic that I’ll be able to accomplish that level of return. To make 3,200 more a month I’ll need to go from making $32,000 a year to about $60,000 tomorrow. That isn’t terribly realistic either. If I don’t account for my rate of return I need to invest about $5,045 a month including my returns from my investments. If I grow the amount I invest monthly at a steady rate from now until 40. I created an excel spreadsheet which assumes I constantly increase my pre-interest income. I can start out at $400 and I’ll need to invest $9,642 on the last month. Every month I need to increase the amount invested by about $47 to get there.

Next, I discount the expected earnings that my current investments will provide. This can include my income from my investments. Next month I have to invest $446.91. If I can manage a 8% (annualized) return (say 0.66% per month for simplicity). I currently have have $6,194 invested. This means I can count $41.3 as long as I reinvest it. I’ll need to cut $5.61 from the food budget next month for investment or figure out another way to earn an extra $5.61. It’ll be better if there is a way to make this recurring. Over the course of this month I’ll have to figure out a way to earn an extra $5.61/month for the next 15 years. That is the goal this month, I could instead manage to come up with an extra $841 next month to invest which would produce $5.61/month. The goal of these articles this month will therefore be to scrounge an increase to my income by $46.91/month in a permanent fashion every month. Due to the increase in investment income each month I can increase my savings by 30 cents less. This means that the amount I have to invest from outside peaks at $3,476 after 142 months of investing.  This means that the most I will ever have to invest will happen in November 2023 when I am 34.