There are some patients who are more difficult to take manual blood pressures on than others. I've found that these steps have helped me:
-Look at their previous blood pressures. Have the systolic bp's all been in the high hundreds? Have they barely hit 100? This will give you an idea of where you will probably hear the first sound at.
-if they don't have a prior blood pressure, one thing you can do is tell the patient you are taking a preliminary blood pressure and will get the real one 2 minutes afterwards. Then instead of holding the stethescope to them, hold your hand on their radial pulse. Pump up the cuff so that you don't feel the pulse anymore, and then let the air out until you can feel the pulse. This will give you an idea of where the systolic blood pressure is. Wait 2 minutes or so before taking their actual bp reading (you can use this time to get temperature, resps, and pulse)
-Watch the sphygmomanometer readout while you are taking the blood pressure. You will notice that for pressures above the systolic, the pin will move down smoothly. When it hits the systolic, it will start to bump down. The link the above poster listed has the blood pressure practice program which shows this well.
For respirations, after taking the pulse, continue pretending you are taking the pulse and watch their breathing. Otherwise, put the stethescope to the 2nd intercostal space, left midclavicular line, and say you are listening to their heart -- you can hear their breath sounds and get the respirations that way. You can also pretend to chart and take their respirations then. For one of my patients whos resps were in the high 30s/low 40s, I was able to see them in the reflection from their door window, and count them that way.
Another thing about respirations. When you first arrive, come in quietly, and if the patient is still sleeping, get their respirations first before waking them up!
hope this helps and good luck