I'm ok with change as long as I know what is going to happen, and there's people I trust.
She has you there, which is a good start for her.
Are there photos to show her of where she is going to live, or can you visit there before to show her where she will be living? (Though once it has your furniture in, it will look different to how it is now anyway)?
Keep to her usual routine as much as you can on moving day, and afterwards.
If she has a special toy or activity that usually takes her mind off things, have that available all day if you can.
We moved with our son when he was 4.5 and it went well. He was very involved with the move and we explained as best we could everything before hand. He watched the removal men with the boxes and was fine. When things felt like they were getting a bit much we distracted him with his then favourite place to sit - my husband's car.
He was absolutely brilliant - especially since the place we moved into was such a dump that I wouldn't let him use the loo on his own for ages. Since then he has been fascinated by houses and watches location location location and all the other house programmes avidly.
I would say that the best thing was that we spent the time with him on the day because the removal men did all boxes etc. My mother was suprised - she thought I'd just send him to nursery and take him back to the new place at the end of the day. I thought this would be calamitous and really stressful for him (and therefore us) as he would think that if he went to nursery he might not come back to the same home.
Be prepared though for your sprog needing to sleep in your bed, etc. Keep set routines as near to rigid as you possibly can and all will be well.