Many partners have their own expectations of how the labour and birth will be for the woman. You may have no expectations or you may have some subconsciously without being aware of them.
Looking at your partner and bearing in mind how she copes with life changes, stress at work, or at home, challenges and pain, you may be able to have an insight into how she deals with the intensity of labour. There are various ways of coping or dealing with stress or the "fight or flight" response. These may include frustration, determination, shutting down and closing off. Use the analogy of how she would be standing at the edge of a cliff, needing a leap of faith to have her baby. Would she run over the edge trustingly, need a nudge or push of encouragement, or would she run back to safety, needing to be dragged over reluctantly?
If it is her first labour there is usually the concern of the "unknown". If it is her second, third or more she may need to deal with letting go of what happened last time (too long, too fast, painful, exhausting, or unwanted intervention). Some women panic in subsequent labours because they are much more painful and quick. This can be a shock if the first birth was seen as a positive experience.
Ask yourself if you have expectations about her not having any forms of pain relief, perhaps you have concerns about your baby and the affects they will have. Do you expect her to have medical pain relief straight away? To make your job a whole lot easier! Be aware that this may be a little out of your control. Talk to each other about your expectations and be realistic about the choices your partner may make.
What do I do if it can't be the way my partner wants it to be?
This may be similar to identifying your own expectations. Find out hers, she may be open to whatever will eventuate or she may have set ideas. Talk about how she will feel if it doesn't meet her expectations.