Learn one tense at a time. Before delving into the following list of resources, it is important to realize that learning each tense separately is essential to fully understanding tenses in English. Delving into too much at once will lead to confusion and frustration.
Go to Buzz-in, which is an online resource focused on teaching tenses, providing the user with online grammar tests and exercises.
Buy an English language book such as Practical English Usage by Michael Swan. This gives a grammar overview and devotes several chapters to the use of tenses.
Hire an English language tutor. You can search ESL tutors board where certified ESL (English as a Second Langauge) teachers offer private tutoring, online or in person, and will help you learn a specific skill, like tenses.
Take a TEFL (Teaching English as a Foreign Language) certification course. While this course was designed as a teaching certification, it is also a good way to learn English tenses. The TEFL certification tests you every step of the way and provides feedback from a personal tutor. It is possible to do a TEFL certification online or in a classroom.
Test yourself. Read books and newspapers and identify the tense in use in each sentence. This will increase awareness, and you can use your grammar book or your tutor when in difficulty.