Helpful Tips towards learning Tajweed
• You must find a Qur'an teacher who has studied Tajweed to listen to your recitation and correct you. Tajweed cannot merely be learnt from books, because the movements of your mouth as well as the sounds are important and only a teacher can correct you and make sure you are applying the rules correctly. Sometimes local Mosques will run classes. Qur'an recitation is a science which was passed down generation by generation through teachers not just books.
• Find a book containing the rules of Tajweed and learn each rule little by little, applying it as you go along with the help of your teacher. There are many concise Arabic books and in English there are some books as well as tapes to help. Look for books with some drawings showing you how to pronounce each letter.
• Listen to Qur'an tapes of reciters who recite very clearly, at a medium or slow speed (like Sheikh Hudhaify or Sheikh Muhammad Hosary) and try and notice them applying the different rules of Tajweed. Repeat after them while trying to apply the rules you've learnt. Try to copy their tone and melody as well and see how it changes as the meaning of what they're reciting changes.
• Try and apply the rules you learn to the Surahs you have already memorised and don't become lazy about reciting correctly. You might have to revise the surahs by looking back at them.