dont know how you started teaching her, but anyone beginning an exercise needs to have a clear picture/example of what you are trying to get them to do. lots of videos of the lifts being done properly can be very helpful, and make her more comfortable. that doesnt mean they should outright copy one of the champs- certainly we have too much of that going on! but rather, watch many different lifters making successfull attemts to get the overall rythym.
also, teaching how to miss should be done early on. she should know that in case she cannot make a weight, its ok to dump it by just letting go. since its a mortal sin to do this in most health clubs today, its worth reinforcing that its ok.
lastly, just reinforcing how this will make her a better rugby player, and if she truly understands how, you just need to call that in for motivation. -g