We all miss a blood pressure every once in a while. Be upfront during the test. If you didn't hear it, say so, don't make up a number in hopes that you are correct. The patient won't be going anywhere...give them a minute and try again.
Don't be nervous about it! I was the first time I took my skills test and I failed. The second time around, I made sure I knew how to do it and didn't stress out about it and I passed with flying colors. You can do it . Practice, practice, practice!
Palpate for the pulse first, then line up the arrow with the artery, put your steth right over where you palpated, make sure the cuff is the proper size, pump up the cuff no more than 20-30 mm Hg above the baseline bp and let'er rip. If you don't hear it the first time say so, deflate the cuff and wait 1-2 minutes.....that's the standard
PRACTICE PRACTICE PRACTICE....even now I sometimes don't get in on the first try....