How does the whole badge-earning thing work?
It says I have none remaining?
Level 7 btw
You primarily earn cards via "drops", which occur on the odd occasion while you're in-game (you don't actually have to be playing; you can just idle in the main menu and alt-tab to do something else). You'll have no drops remaining for F2P games if you didn't spend $9 in the in-game store prior to the trading cards being implemented (or, in the case of TF2, didn't own a copy prior to it going F2P), whereas for paid games, you'll either have an amount of drops equal to half or half+1, depending on the total amount of cards available (e.g. if a game has 8 cards, you'll get 4 drops; if it has 9 cards, you'll get 5 drops).
As for the cards themselves, there are regular cards and rarer foil cards, the latter of which you can flog off for a pretty penny if you beat the market crash; additionally, you can also earn booster packs, which are a set of three cards, with a chance of a foil, that "drop" infrequently as long as you've signed into Steam once in the past week. Obviously you cannot complete a set with the limited amount of drops, so you're encouraged to either trade for or purchase from the Steam Market the missing cards. You can gain drops in F2P games by spending money in the in-game store, but given that you only earn a single drop per $9 spent, it's far cheaper to just buy what you need from the market. While cards disappear from your inventory when you craft a badge, once you've "maxed out" a certain badge, they will remain in the badge section of your profile, so you can view them at your leisure. (Valve will soon be implementing a virtual binder wherein your cards, whether present in your inventory or having been used to max out a badge, will reside.)
Badges can be "crafted" either by completing certain tasks (such as the Steam Community badge) or "spending" a complete set of cards. The ability to "level up" promotional badges (i.e. those not based on cards) varies, but regular card-based badges can be taken to level 5, while the special foil badges can be crafted just the once. When crafting a badge, you earn an emoticon, profile background (both related to the game in question), a
Mysterious Card and 100 XP. XP in particular is used to "level up" your Steam Community profile, and with each level you gain an additional five friend slots as well as a showcase slot to show off something of your liking on your profile (rare/favourite games, games/DLC owned, achievements earned, etc.)
Edit: If a badge is not showing up in your list, either because you don't own the game in question or haven't spent enough money in the in-game store, it will appear after you receive a card pertaining to it. For instance, I didn't spend money in Dota 2 prior to the trading cards going live, so the badge didn't appear in my list until I began buying Dota 2 cards.
Edit edit: Sorry, I can't type tonight.
