New cherry laurel screening hedge advice

Hi Everyone,

New member here! I am looking for some advice regarding my newly planted cherry laurels.

I have read through the famous laurel thread by befuddled twice now, once when we just had them planted and again just now and I have almost convinced myself that I need to cut them down quite a bit to ensure the best results down the line.

We had someone come and plant them for us towards the end of April as we had no clue what we were doing.

Here they are at the end of April just after they were planted.



And here they today two months later.



They seem to be doing ok but there is a few that have branched with no leaves at all in places as they turned yellow and fell off, I think this may have been due to the heat or me over watering them as since I have stopped watering them as we have had quite a bit of rain they have recovered.

I could just do with some advice about when would best to prune them and how do I go about doing it, or is it just a case of simply cutting all of the branches down by about half with secateurs?

Thanks,
Nathan.