sugandh?? Those seem specific to one sub-discipline of EE. Host, that question is really vague. The best I can do is give you a vague answer.
Math - (complex numbers, linear algebra, Boolean algebra, series and calculus)
To get better at math? Take classes with teachers known to be hard and force yourself to get an A.
Programming - (C, Java, VHDL, Verilog, Assembly, MATLAB, and the general ability to learn any programming language in a short period of time. Also to be able to switch between writing codes without getting confused.) To get better? Learn a lot of languages.
Electronics - (digital, analog, integrated, op amps, transistors, RLC circuits, Microprocessors/controllers, FPGAs, CPLDs, DSP, Communication, robotics/mechatronics, control systems, power systems, part selection, soldering(maybe) and I'm sure I missed something) To get better - Practice if you already know and learn if you don't.
Teamwork - (design process, ability to communicate ideas, technical writing, ability to work with other people effectively, ability to lead, self motivation etc...) To get better? practice
There.. I split it up into 4 categories. sorry 3 wasn't possible.