Unfortunately no one really knows, different faiths believe different thing. The scientific answer is you cease to exist. you body remains but your brain is gone therefore your consciousness and what makes you you is gone as well. I believe in reincarnation, other believe in a heaven or hell type concept. You need to do some soul searching and come to your own conclusions about the afterlife.
Regarding your comment about "trying it out" I hope you are not referring to suicide. Life is constantly changing, the bad will make way for the good. You matter, even if your mind is telling you otherwise, so many people will be effected, even if you don't believe it to be true. Besides, even if their reincarnation, heaven, or nothing, this lifetime will end forever. Please, if you are contemplating suicide, talk to someone, doesn't have to be a loved one, there's help lines you can call and just talk. It's surprising how saying your pain out loud to a complete stranger really does help.