There are many main components involved in being good at PVP, here they are:

1. Good Amour
Good Amour is essential, obviously, to protect you well when being hit. And enchanting your armour is even better, use your armour at all times.

2. Keep Space
You can't always be very close to your opponent as you don't want to get hit multiple times in one go, Keep your space, And plan every hit and move.

3. Know you fighting area
If you know your fighting area, you know where to go when in a tricky position and potentially get the right hits, also to miss hits from your opponent.

4. Keep calm and carry on
If it seems to you you might loose, carry on. And have the motivation in you to finish the fight and win in. Another good piece of information is if you loose, it doesn't matter. You'll gain experience of PVP and get better.

5. Good kit and spares
Having good kit is essential, and having spares is too. If you loose a sword in a fight you have a spare. It's the same with armour.

Thank-you for reading this article, and have fun! :D