Good answers in this thread. Really can't go wrong with 80-100% equities while young and without much money.
At some point you will have enough money to be very unhappy about the thought of losing up to half of if for possibly many years, and at that point you should consider bonds more seriously.
For me anything under 200k is not enough to worry much about an up to 50% drop so I'm ok with just an emergency fund and the rest in stocks. For others, this will be stressful and they will want some bonds before that point. For others still, they can handle 500k or more all in stocks (although I doubt there are many who actually will be ok with it, despite many thinking they will).
A simple rule to start with is, consider your total amount of money for investing. Then think how much in actual dollars you could tolerate it dropping to without freaking out and panicking. Double the drop and that is your equities. Repeat this every year to adjust you ratio to your new balance.
For example
- with 100k I'm ok with it dropping by half, so my AA would be 100/0
- with 200k I'm ok with it dropping to 120k, so my AA would be 80/20
- with 300k I'm ok with it dropping to 180k, so my AA would be 80/20
- with 500k I'm ok with it dropping to 320k, so my AA would be 72/28
etc
These are just my own numbers. You would need to do it for yourself for your current balance.
And you need to use your actual dollar amounts, because in a crash you will see those actual dollar amounts come off.
One thing I've realised is, despite all the people on this forum saying 100% stocks, don't just blindly follow the crowd. Don't to be afraid of having some bonds. 10% and even 20% does not reduce your returns much but lowers volatility a lot, and being able to sleep well during a market crash is the most important part of investing after diversification.