First, you'll need to get a copy of the game.
Since Future Invaders isn't published yet, the only way to get it is by downloading the cards from this website and printing them yourself.
To learn how to play, you will have to read the rules. While Future Invaders might seem complex at first, its rules are actually simpler than many other strategic card games.
If anything is unclear or ambiguous, you can ask the community for help on Discord or IRC.
Enjoy the game, and have fun!
Your goal in Future Invaders is to destroy your opponents' bases, while protecting your own. You do this by drawing cards, some of which are ships and structures, with which you populate a small grid in front of you.
Ships attack your opponents every turn, and both ships and structures protect you from enemy attacks. You can also play action cards, which change the state of the game, and reaction cards, which alter actions or prevent them from happening.
Most cards cost resources, which you earn by having ships and structures on the grid. There are five different factions, each with their own unique resource and gameplay style. Mixing factions is allowed, and encouraged.
The game can be played as a regular 1v1 battle, as a multiplayer battle, or in draft mode. Pre-assembled decks of cards are suggested on the website, to get you started.