not sure what sort of advice you want for the IHm but stress is made worse by lack of control re surroundings etc I would advise that you explain exactly what you are going to do and assure her that you will stop the treatment at any point if she feels uncomfortable - taking time to chat first wil help with her control and hopefully avoid a panic attack I also think you should advise of the possibility of a healing crisis after a treatment but make it clear that this does not have to happen and agree that she can ring you if she does have a head ache or whatever after
also stress the importance of following the after care regime - lots of water and rest etc for 24 hours
and as after care advice I would suggest that she explores other things , yoga tai chi, diet , meditation etc to find something that helps which she enjoys - you could also teach her some breathing exercises
oh i woudn't use too much pressure during the treatment , firm but gentle strokes
good luck