To start developing on Android you'll need the following:
- Android SDK
: Software Development Kit, which contains the necessary tools and compilers to create your apps.
- Android ADT
: Android Developer Tools, which expands the Eclipse programming environment to develop Android apps.
- Learning Java
: Since android apps are programmed in Java, knowledge of this programming language is required.
You have to make the Android developers website a frequent destination for your learning-oriented visits when you plan to become an Android deloper.
Finally, remember that Google is your friend. Almost certainly another developer has been right where you are when you block. And given the popularity of Android and a great community, chances are you will find the solution. Otherwise, you can ask the community. Programmers are generally a friendly bunch.
Good luck on your journey of development and learning! Programming is a skill for life, remember not to rush things and not give yourself less than one (1) year to learn.