Do you like playing computer games?
You feel pleasure while playing computer games?
What if you could make money from that and you won't have to work at full time?
Great idea! not enough that you are relaxating, you also have money from that!
At the beginning
Not every idea is for everyone - depends on ethics, experience and PC of course. However, every player who want to make money, will find idea (I hope so :) )
At the beggining something obvious - streaming your game plays, showing off with it. However, that's not the best idea because to have money from that, you have to be at least a bit famous. It takes time and it's not for everyone - The most watchable platers are pro players, so to make higher amount of money, you should be one of the best players - it takes time.
By this method you can make additional money only, because to make money by boosting, you need a lot of time. If you like playing computer games and you are good, experienced player, you can do that, but if you don't have a time, you shouldn't.
Dropping and selling items
This is largely true for mmorpg games. If you dropped very nessecary items to other players but not for you - you can sell it. That's also cheap version of making money, but you can add some to your pocket ;)
For example in Realm Of The Mad God you can buy maxed character or untradable items, potions and way more. It's very cheap but some of players if are lucky - can make higher amount of money per hour than in normal job. As always - depends ;)
It's easy way to make money - firstly you have to know if prize of item is lower or higher than market prize. By that you could make much higher amount of money than in full time job but it takes time. For example if you see a knife in CS:GO which is cheaper than others by 30$, don't be afraid - buy it and resell it! By this method your money is working for you :)
That's not ethical method, but really worth.
This method is also largely true for mmorpg games. You can set bots which can drop items which are very nessecary, for example to uppgrading eq. 1 bot is dropping for example 20 stuffs in hour, 1 costs 70k and you can buy 10kk/3$. By setting 10 bots, in 1 hour you could make about 3$ per hour. That's not good enough, but by settings more bots you could make larger and larger amount of money. That's really worth option of making money but not for everyone.
Exp and sell
It depends on exping your character and by gaining a character worth selling, you can earn money by that. But not exping on your own... It takes a lot of time and it's not really worth. You have to set bots which will exp your characters and you will have a lot of sellable characters in one moments. Of course bots are banable so you have to prepare for getting some bans and be patient :) It take time but it's worth, but as I said before - it's not for everyone because it's not ethical :)
That the most not ethical way of making money from games but better paid than Twitch!
This method is for really advanced people or for those who watched a tip on YouTube for example :)
It depends on looking for game errors. Example:
In Nostale you could receive infinite amount of times prize from a quest in Packet Logger. By this quest you are getting exp (you can still do this quest, but can't repeat this - glitch was deleted). By repeating this, a lot of people has gained 99 lvl from 85 in few minutes (In normal exping like killing mobs etc. it takes months). For cheaters, lvls were drifdown, part of accounts were banned but part of players sold accounts with 99 lvl and earned by this a lot of money if they had few accounts.
By playing in games you can earn a lot of money if you know what to do and you want do it ;)