You can make more with $400 than most newbies on this forum ever made in their life.
You can easily make between 1% and 5% per day on a single trade. If you stay active for 6 - 8 hours, you can easily compound and have several of those trades in a single day.
Let's say you manage to get 2% realistically on a single trade:
$400 x 1.02 = $408 thus $8 profit for doing just a few clicks.
Usually there are two to three lows/highs in a single day that can make you 2% easily (when trading BTC that is, from my experience).
So you are looking at the next formula:
$400 x 1.02 x 1.02 x 1.02 = $424,48 --> you just made $24 in a single day.
The next day, using $424 and another 3 trades making 2% will earn you about $26.
If you keep this up every single day, after a single month you have transformed $400 into $720.
After 3 months you will have $2330.
This is way more than +95% of the people earn here from Instagram, Pinterest, Twitter, Facebook, SEO, ...
But there is a risk -- trading is risky -- and if you don't know what you're doing you're just gambling.
Cheers