How to be a good developer? And how to crack codejam tournament of google??

Answer 1

to be a good developer:
learn your language(s) of choice in depth
learn the librarys/frameworks you are using in depth
learn about desig patterns
learn about algorithms
learn about data structures
maybe learn some domain specific math, graph theory is always useful
and of course code a lot

Answer 2

In addition to programming skills, communication skills are very important. You have to work as a team for many projects, and you have to understand, translate, and deploy what customers want.

Answer 3

Practice!
Practice more!
Take care of your health, eat and sleep well.
Practice.

Answer 4

For cracking any coding interview or to become a success programmer you need to practice programming so as to refine your skills and improve the problem solving ability.

When trying to do so there are vast platforms available online where you can do the practice online. One of them is Codefights.com

The platform is specifically created for software engineers to practice coding for interviews to get tech jobs.

Give your skills a try once.