It’s no where near as hard as starting the pump – I couldn’t stop looking at it and smiling for the first few days! – it’s just a bit quirky so you need to get used to it. I’m excited for you now!
It doesn’t transmit very well through your body – I tend to wear my sensor on my back, and have my pump clipped to my waistband at the side or in the side of my bra and that works. If I have the sensor in my back and wear my pump in the middle of my bra at the front it loses signal, it doesn’t seem to be able to get through my body. Wearing the sensor on the left of my stomach and having the pump on the right is no problem (unless you’re very pregnant when someone was telling me it doesn’t get through/round the bump very well!).