There are restrictions to your account - main issue being that you have 50 inventory slots, which disallows you to stock at least 1 of each weapon since there are more than 140 unique weapons in the game. This means that you'll need to be more selective in which items you trade with whom, and you'll be spending more time shopping for trades than actually completing trades. It slows you down and severely impacts your overall ability to turn a profit.

Scrap Bank.

All you need to do is scrap bank, which means that you are selling 1 scrap of metal for 2 weapons that are usable in crafting. Then sell each of those weapons for 1 scrap or 2 weapons that are usable in crafting. So each trade will net you 100% ROI - you'll be doubling the value of your items in each and every trade you complete.

The only thing you need to be careful of is trading for weapons that are difficult to find buyers for -
you don't want to be stuck with items you can't sell. If you do, however, get stuck with 2 weapons that just don't seem to sell, you can craft them into a scrap just as long as they are within the same class.

So the secret sauce is in learning which items people want and are always looking for. The unfortunate reality is that these are always changing. New updates may nerf or buff certain classes or weapons, and people have different preferences when it comes to what they want to use.

For all of you who say this doesn't work anymore - I'm still using this technique in trading. It's easier for me since I have a premium account and have 2000 inventory slots, as well as 920+ refined at my disposal, but nonetheless it still works. There's no reason why you can't make it work too.

Can't find anyone on community trade servers that's generous enough to start you off with a scrap donation?

I'm right here. I'll give you some metal, but here's the catch:

You need a friends list greater than 20 people, and you have to invite them all into my Steam group (they don't have to join). Once I see your invitations, all you'll need to do is place your trade URL on your own profile or on the group's homepage comments section.

The instructions are in the group profile: https://steamhost.cn/steamcommunity_com/groups/FreeTF2Metal

I give between 1 scrap and 1 reclaimed to people who actually follow the instructions. Once the trade finishes, I'll be posting a screenshot of the trade to provide proof that this is no BS.

I already have about a dozen screenshots of proof (unlike literally every other giveaway group).