I don't know if you're serious or not, but I'll answer as though you were.
What does it mean to be Christian?
1. Acknowledging that you've screwed up at some points in your life, just like everybody has. You may not be the best or worst of humanity, but if you look at yourself honestly, you know that you're not perfect.
2. Realizing that those screw ups (sin) have a direct correlation to death. People die because people sin.
3. Desiring to be free of your personal history of sin and the natural consequences, and desiring to live a better life.
4. Understanding that the one person who lived a sinless life is Jesus Christ, able to be sinless only because his nature was both human and God at once, and that by his own free will he chose to die in your place, taking the consequences of your actions long before you were born, for no other reason than love for you as an individual.
5. Choosing to trade in your old life, with all the sin and self-interested decisions, and trade it for a new one. Your new life is something where you consciously decide to pursue a life of real integrity with God's help (since that level of integrity is something no person could accomplish alone)
6. Sitting down and having a conversation with God about all of this and asking him to be a part of it all.
You don't need trinkets, you don't need to worship in a particular way, you don't need to suddenly become missionary extrodinaire - lots of those things are external trappings that have been added as part of a religion. The core of being a Christian though, is what I've spelled out above. You'll find that it's common across all Christian denominations, phrased in different ways.
Christians have a tendency to be self-righteous and beat people over the head with a holier-than-thou attitude. Holier-than-thou could not be further from the truth. The very place you start is a humbling place: coming to terms with the fact that you aren't perfect and that's a problem you can't ignore. The place you end up is humbling as well: you can't reach your goals alone because you by yourself don't have the ability to overcome your tendency towards wrongdoing. Any Christian that acts uppity about how "good" they are is failing in a crucial point in their faith.