Car pulling right when braking

[Jess&Chloe]

Clio 06 1.2 16v
My Clio is pulling to the right when braking and also there is the odd clunk from either side under braking and when pulling away. I mechanic drove it and said sticking calipers and was supposed to take the brakes apart and look at it for me but he's gone quiet and not replying to my texts so I'm planning to look at it myself.
As far as I'm aware disks and pads are OK.
What should I be looking for when I take the brakes apart?
Any tips or advice, or any good YouTube videos that can help?
watched so many vids I have a good idea how to remove the brake pads and calipers but they don't go into much detail on problem solving.
Thanks in advance

 

[Louis]

It'll most likely be the sliders that have seized. I'd buy the kit off ebay in advance before getting to them so you can fit fresh ones whilst it's apart.

Fairly simple job, think there's a guide on here.

 

[Jess&Chloe]

Brilliant thank you, just had a quick look on eBay, unsure if I need the 62mm or 72mm pin kit, anyway of measuring them without taking it apart first?

 

[Louis]

72mm is for vented discs. 62mm is for single plate discs