Here is how to do it: 1. Learn the forms of the regular verbs first of course. 2. Use the internet or your textbook to find lists of the most important irregular verbs. Write each verb on one side of a card and on the other side write all its forms e. g to write/I write, I wrote, I have written etc. Read through each card memorising the verbs. When you have a spare 5 minutes read through a few of your cards and test your knowledge. Do this for a week or two and you will have mastered the verbs.

Remembering which verbs are regular and which are irregular is very difficult and can only be accomplished through repeated practice. It's one of the most frustrating things about learning English