for any language, it's a matter of using the language...
incorporate english into ur daily life... communicate with ur classmates/friends in english... although it will be difficult at first as the tendency is to speak ur mother tongue...
read english books... pick up books of ur personal interest... like if u like buses (if i recall one of ur earlier threads), go library and select such books to kickstart ur reading habits. read newspapers also.
as for maths, there's really only one method. practise & u'll get the hang of it.