how to improve game above 1500 rating??

Hello, I am Lovish Verma from India.. still I am 1500 rated player officially by playing rated tournament without any coaching or classes.... so at this time my mind is at shut down point.. my gaming strength not improving but its decreasing day by day... I am so upset for this.. Please give me tips tell me how to improve my game.... www.chess.com is a very good initiative for me... but at my side I am not enough money to subscribe this..... you know sir in India there are many chess players and his gaming style is so impressive but they have not money to spend on chess.... so they all are stop at a point... please give me tips to improve my game to above 1500.....