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Well... it is really inappropriate to create a new thread for a SIMPLE QUESTION (does that ring the bell?).
Anyway, I will answer.
You need to have your sprite INDEXED. Check the Documents and Tutorials section for further info.
You need to get a tool called UnLZ.GBA. Check out the Toolbox section, in particular, HackMew's Tool Factory thread. There is a download link in the first post.
Now, find the way yourself, as many others before you, or check a guide in Documents and Tutorials section. Author of the thread is Scizz, try to search amongst last pages.
Next time, don't act immaturely and follow the rules, that is my recommendation.