Our wonderful practice nurse does mine, and there is really nothing to worry about. If you have a needle phobia, say so immediately you walk in; they are trained to cope with that.
She asks my weight (or she may weigh you), she prods my feet - very gently! - with a small blunt pin, or tickles them with a filament, while I keep my eyes closed, to see if the feeling in them is correct, and she checks that she can hear a pulse in my ankles to make sure the blood flow is good.
She then checks my blood pressure, and after that takes blood samples. I always go fasting, but this is not always necessary; make sure you tell her if you have eaten, just so that she (or the doctor) can interpret the results correctly. For me, the blood is to check HbA1c, kidney and liver function, a full blood count, vit B12 & folate levels, thyroid (I'm hypothyroid so I would have this whether or not I was diabetic) and cholesterol - a full blood lipid levels test.
I usually take a first-thing urine sample for my annual review. I get the sample bottle from reception a few days before the test. I use a plastic cup to catch the sample - eg a water fountain type cup, which squashes easily to make a pouring lip to transfer into the sample bottle.
Most of the results are back within 24 hours, but the HbA1c takes longer with us. I usually go to see the doctor about a week later to discuss my results - whether he wants to see me or not! - and I always get a full print-out of the results for my own files. I even have the receptionists trained for this, so I get the print-out as soon as I walk in, and read them while I'm waiting. Then I know if there's anything I want to talk about, which saves the GP's time. Usually all's well; in fact, now I understand what my readings mean, I often don't need to see the GP at all.
Our morning surgery is 'walk-in'; no appointment necessary, so sometimes you have to wait a while to see the doctor.
As a separate appointment, my eyes are photographed annually to check for retinopathy; people from our local hospital bring a mobile unit to the surgery for that. You may have to go to the hospital clinic for yours, depending how far away it is.
Hope this helps!
Viv 8)