Here is a mind map of irregular verbs organised into groups (click on it to see it in full). We can divide English irregular verbs into three main groups:
Group 1: the infinitive, the simple past and the past participle are the same (eg, cut/cut/cut)
Group 2: two words: either the infinitive and the past participle are the same (come/came/come) or the past simple and the past participle are the same (buy/bought/bought)
Group 3: three words: the infinitive, the past simple and the past participle are different (see/saw/seen)
The second and third groups can then be divided into sub-categories. Putting them in mind-map form makes them easier to organise and subsequently to memorise.
Mind mapping is a great way to test yourself. Take a blank piece of paper and start a mind map with ‘irregular verbs’ as the central theme. Then draw three branches and write ‘one word’ ‘two words’ and ‘three words’ on the branches. Try to write as many verbs as you can remember, then check to see which ones you missed.
There’s also a PDF that you can download of irregular verbs in groups