What do you do about grey roots when you only had highlights 5 weeks ago?

[Trickymoments]

I've had highlights for years but now the greys are starting to appear. I am conscious that my natural hair colour is so dark against the block of highlights & now there's the added grey streaks! I love highlights but can't afford them more than about every 3 months so what do I do with the roots in between? It looks a mess!

I've used this is in the past - get different shades to suit. Sure there's plenty other brand names.

https://www.amazon.co.uk/COLOR-WOW-Cover-Medium-Brown/dp/B00FYSZDQ4/ref=sr111ssit?s=beauty&ie=UTF8&qid=1476022593&sr=1-1&keywords=color+wow

My hairdresser just does it so the grey blends in,I think she uses 3 different colours.

I use this www.boots.com/en/Toiletries/Hair/Colourants/Root-Touch-Up/

Second root touch up

I touch up my roots with an ash brown nice and easy/clairol. I do this every 3 weeks and it keeps it fresh so I only do highlights every 3- 4 months

Kennington I'm very interested in the diy root touch up as I just don't
think I can afford all of this done at the salon.
Is it a tint that you use, a semi permanent or permanent? Do you put it on the roots all over or just on the parting line? This could be the answer I'm looking for but I'm nervous about getting it wrong by doing it myself.
Anyone else do their own roots at home & highlights at hairdressers?