You'll need to invest some money and then waiting months to gain profit (could take days if you are lucky).
If you can't or don't want to then leave this thread.
Well this is easy af!
Just invest some money in csgo stickers and you'll get a guranteed profit. Yes this will take a few months but
it is worth it. As example I've bought last year about 100 stickers from a major league for like 0,08$ each and after
a few months I've sold them for 0,3$ each. So I've spent 8$ and got 30$ so 22$ profit.
This isnt much but as I said this was just an example. I've made about 250-300$ so far doing it.
You can do your own research on which stickers you buy but this are my recommendations:
(highly recommended) https://steamcommunity.com/market/listings/730/Sticker | Flash Gaming | Boston 2018#
(highly recommended) https://steamcommunity.com/market/listings/730/Sticker | Astralis | Katowice 2019
(highly recommended) https://steamcommunity.com/market/listings/730/Sticker | FACEIT | London 2018
Now you have some examples which stickers you should buy. I highly recommend to buy autogram stickers from famous/popular pro players.