ive been breeding for years and always go on day 10 or so either with AI or natural matings.
i have one female i would like to progesterone test  as she has missed to a well proven stud dog.
can some kind person give me advice onhow i go about it please as im complete novice when it comes to this.
thank you in advance.
i am inthe uk.

I use Idexx. https://www.idexx.eu/united-kingdom/form/reference-laboratories/progesterone-order/progesterone/ You get the blood sample drawn by your vet and then take or post the sample to Idexx. If you post it you need to use next day special delivery. You'll get the result on the same day they receive it. The levels are as follows :-
<3.0 nmol/l – re-sample in 3 to 4 days
3.0 to 8.0 nmol/l – re-sample in 2 days
9.0 to 15 nmol/l - mate in 2 to 3 days
15.0 to 30.0 nmol/l -  mate in 24 to 48 hrs

>30.0 nmol/l  - mate asap
>60.0 nmol/l  -may be too late

You need to go to your vet and it's best to make an early morning appointment to give the sample max time to get to the lab that day.  It is also best not to feed your female before progesterone testing as it can skew the results some, if you do.  (Vets don't tell you this, by the way!). 

Usually the vet sends the sample to the lab.  We got the result about 4pm the next day - so a sample taken on Monday morning and we got the result Tuesday at 4pm.  Bear in mind this time delay.... Also we could not test on Saturdays because we wouldn't get the result until Monday and it would be pretty useless that late.  And our vet is closed Sunday and bank hols, so couldn't test then either.

If you want to do things properly and by the book, it is best to do one test around Day 5 - just to make sure you don't have a really early ovulation.  As you've missed before, I'd suggest you do that for sure.  Usually a Day 5 test would show things just getting started but not going anywhere that fast.  Once you have submitted one test, the lab will recommend what day you do the next one. 

This is the table I've used:

0-2 Nmol or 0- 0.6ng   Baseline  

3 - 6 Nmol or 0.9 - 1.8ng minimum two days to ovulation but could persist for up to a week. Minimum estimated breeding 4-6 days

7 -12 Nmol or 2.2 - 3.7ng minimum one day to ovulation. estimated breeding window 3 -5 days

13 - 18 Nmol or 4 - 5.6ng ovulation impending or just occurred. Estimated breeding window 2-4days

19 - 31 Nmol or 5.9 - 9.7ng ovulation recently occurred. Estimated breeding window 1-3 days

32 - 64 Nmol or 10.6 - 20.2ng Ova mature Optimum fertility. Estimated breeding window 0 - 2 days

65 - 90 Nmol or 20.4 - 28.3ng ova mature but ageing, decreased fertility. Breed at once

90Nmol plus or 28.3ng plus - too late

It is also definitely worth doing the CHV Eurican Herpes vaccination - if you are doing a progesterone test Day 5, you can get the jab done at the same visit.  This is because sometimes a bitch does ovulate and conceive but then absorbs the litter due to herpes, before you even knew she was pregnant.  You will need to tell your vet ahead of time that you want the herpes jab, so they can order in 2 doses for you to have ready.

I was on an American breeding site and they often use idexx too and their recommendations for mating are actually earlier than ours on the list you've posted.

Trying to find the screen shot I took of it

> If you post it you need to use next day special delivery

2/3 Times I've used the free post card envelope that comes with the kits and they got there the next day, even when delivered on weekends.

It depends where you live as there may be somewhere near by that do progesterone testing.
When I have done it I get the blood drawn at my vets in the morning then take it and drop it at the lab attached to the vet hospital ans get the result by 3pm the same day which if you are travelling abroad etc is much better and gives you more time to plan.

Also have a look at ferning.  I've progesterone tested in the past, and, although it's accurate, the delay in having bloods processed and getting results, has made it awkward.  Ferning is done simply with a saliva sample from the bitch, and a microscope, the results are instantly obvious.

I had a lot of trouble with ferning and it really didn't work for me.  It's been studied in research and found to be very unreliable. 

If you want a way of determining fertility at home, learning how to do slides and cytology is best.

Worked brilliantly for me with my bitch, and with a very knowledgeable stud dog owner who has used it themselves. In conjunction with physical examinations and the stud dog indicating she was ready, we got it spot on and two successful ties. She’s currently laid across my knee with a tummy full of pups

"But fertility experts warned that saliva tests have a history of being unreliable.
Jane Knight, Fertility Nurse Specialist at the Zita West Clinic said: 'A study of saliva testing devices published in the Lancet found that 8/10 post-menopausal women and all 10 men tested positive for ovulation!
'They concluded that the saliva test is unreliable for predicting the fertile time and its use should be discouraged.'

http://www.dailymail.co.uk/health/article-2221387/The-new-ovulation-kit-uses-saliva-determine-woman-fertile.html#ixzz4y2DAvkMR

Obviously women and not dogs, but it works on the same principle...

I'm sure I read somewhere you could use a human pregnancy test on a dog (as in boy, not girl), and it would be positive for pregnancy? Something to do with different hormones.  In the same way, I'm sure it can't be exactly the same for saliva testing between humans and canines.  In any case, it worked a treat, and the ferning was very obvious under the microscope.  The day she sort of boiled over, and we could possibly have got a third tie, the stud dog was indicating she was still within the right timescale, but with two successful ties, and my bitch not being cooperative, we left it at that.  I can't post the images but they are incredibly interesting, going from a very slight indication of a fern frond or two, to something like an exponential view of fern fronds, to something that resembled a chemical symbol made up of hexagons on the last time we tested.