PandaMojodium

Chances are, I need more information, if I'm linking you to this page.

1. I need your error messages. This might seem obvious to most, but not to all. They have meaning, and if they don't tell you exactly what you did wrong, it will tell you the exact symptom which can be used to figure out the problem — unless the compiler has gotten horribly confused, in which case they still hint at how it's confused. The error message alone is enough for me to figure out exactly what the problem is without source code 50% of the time with newbies at least.
2. For runtime errors, I need your symptoms. How do you know you have an error? What is the exact copy & pasted error message? Do you have a stack trace of where it occurs, and the relevant source code for that area?
3. I need your source code. Again, seems obvious to most, but not to all. If I cannot figure out what the problem is from error alone, I need to inspect your source code for the cause. I need the code around the line of the error — this usually means at least the entire function, probably the entire class (if any), and still pretty likely the entire file. While random code dumps of badly organized source will probably be ignored, so will posts lacking any source code.
4. I need your actual source code. Copy & Paste. If you're simplifying code, try to make sure it compiles and actually exhibits the problem. It's quite annoying to spend time trying to find a problem in some source code, only to find the poster hid the problem with psuedocode that doesn't exhibit the problem, or accidentally chopped out the actual problem area.