To perform a Trade-Up simply click on an item in your inventory that is Civilian, Freelance, or Mercenary grade (if from a contract reward), or Mercenary, Commando, or Assassin grade (if from a case collection). Then from the menu that pops up select 'Mann Co. Trade' and click on 'Item Grade Trade-Up'. You then select 9 more items of the same grade to trade-up with send in your items!

What you get depends on what you trade-up with.

Rarity Tier
What is guaranteed is that the item will be from the next highest rarity tier. For example, if you trade in 10 Mercenary-grade items you will receive a Commando-grade item from the trade up.


Quality
You can do a Mann Co. Trade Up with regular items or 'Strange' variants (but you cannot mix regular and strange items in a single Trade Up). If you Trade Up with regular items you will always receive a regular item, and if you Trade Up with Strange items you will always receive a Strange item.


Collection
In a Mann Co. Trade Up you are allowed to mix items from different collections as long as the items share the same rarity tier. The new item you receive from the Trade Up will always belong to one of the collections you traded in. For example, if you trade in 10 Hickory Hole-Puncher Pistols (from the Teufort Collection), the item you receive will be from the next highest rarity-tier in the Teufort Collection.


Wear
If you are Trading Up with Decorated Weapons they have a 'Wear' attribute that determines how many scratches/stains/blood splatters etc. are on the weapon. In Mann Co. Trade Ups the wear of the new item will always be the same as the wear of one of the items that was Traded Up with.

In order to tailor a Trade Up to suit your desires you need to understand in more detail how a Trade Up is done. Unlike in CS:GO the process is actually rather straight-forward. When you send off your 10 items one of them is selected at random to be 'upgraded'. Lets take a look at an example:

Trade Up with:

AND



You will receive:

OR


So if you were hoping for a Factory New Teufort weapon you are out of luck! If one of the Teufort weapons is randomly selected for 'upgrade' it's wear value will carry over to the new weapon. However, if you want a Factory New Craftsmann weapon this is a good Trade Up because 50% of the time the result will be a Factory New Craftsmann weapon!

This means if you want to be guaranteed a Factory New Craftsmann weapon you will need to Trade Up with 10 Factory New Craftsmann weapons. Conversely, if you want to at least have a chance at receiving a Factory New Craftsmann you need to make sure to include at least 1 Factory New Craftsmann weapon in the trade up (to give you a 10% chance), and then maybe fill in the other 9 slots with (cheaper) worn weapons.

Yes. There is a tool called the 'Civilian Grade Stat Clock', which adds a strange stat clock to a Civilian-grade weapon. At the time of writing performing a Trade-Up with 10 Strange Civilian-grade items is the only way to obtain Strange variants of Freelance, Mercenary, and Commando-grade weapons from the Teufort, Craftsmann, Harvest, and Gentlemanne's collections.

Yes and no. The same variation in skin texture placement, scratches, blood splatters, and stickers can be found among Trade-Up items, and they look and function the same in-game. Outside of the game there do have a couple of different attributes. Firstly, they all have a different origin attribute. Secondly they all have an attribute that tracks how many items were traded-in to make the weapon which is visible only in 3rd party backpack viewers (e.g. tf2tools.net).

Doing a Trade-Up is essentially a game of chance. After reading this guide you should be able to design Trade-Ups that are likely to produce items you want. Whether it's profitable or not is less easy to determine. Sometimes (especially after a new collection is released), it might be easy to identify Trade-Ups that could potentially yield an item that is going to be rare/sought after and could sell quickly for a good price. However, most Trade-Ups cost more to do than the value of any item you could possibly get from that Trade Up. That said, there are often Trade Ups with good potential for profit if you are willing to take the time to look for them and take a few risks.