In order to use the Dmarket platform for trading services, the first thing that you need to do is connect your Steam account to Dmarket. This is very simple to do. First, click on the "Log in" image in the top right corner and choose Steam. This will open a new window and ask you to log in to your Steam account which you can do by using your steam username and password. There are other sign-in options available as well, such as twitch which will require your twitch information, or email which will naturally ask for your email address. Once you agree to share your information and are successfully logged into Dmarket, you are free to browse the market, buy or trade any of the skins available, new or old.
Let's say that you are trying to buy a new item for yourself, a brand new doppler knife. In order to do so, you would have to either browse the skin menu or use the filter system or the search bar on the website. Once you find the item/items that you are looking for, in our case, the new doppler knife, click on the image of the knife that you would like to purchase. You can also the "i" icon in the corner of the image to display the additional information about the new skin that you wish to get. Once you are satisfied with what you see and have chosen the skin that best fits your needs, simply click on an image of the "Buy button" and your transaction should be complete provided that you have the funds and you will get a new doppler knife added to your inventory and you can freely equip it in the game.
Buying a skin on the Dmarket platform is very simple and selling one is equally easy as well. In order to put a skin on sale, simply click on an image of a skin in your inventory that you wish to get rid of and click on the "Sell now" button. Selling game items somewhat differs depending on your preferred sign-in option, but it is very straight forward in any case. It always involves selecting the skin by clicking on its image and then selling it by pressing a button.