I agree with the others users recommendations. Reading will help you a lot to discover new ways of writing. However, another things that help you is practice. Try to write as much as possible if you want to improve. Actually, you can use this site for that purpose so others users can give you a hand with corrections or hints to get better.

http://www.italki.com/entry/495794

   At first Aierfar,  make sure that you have at least a little confidence in writing textual English when using the "Most Common"  words in English.  These can be found  listed on the Internet  as

the "Dolch List".  If you want some assistance  in the construction  of basic sentneces,  to develop your strength, let me know.

and anything els?  my English text is so poor(>_<)

by paying attention to the S-P-O rule (subject, predicate, object). :D

by reading english books