Energetically speaking, there are two main approaches to a reflexology treatment, and it's down to the skill of the therapist to ascertain which one is best. One can choose to act according to a non-interference principle, as simple 'catalyst': this is when there isn't really an interaction between patient and therapist. The therapist 'lends' his/her energy as a medium to support healing. The mere 'presence' of the therapist is enough to help the healing process, the treatment being the medium. A second avenue is the one of active release, where the therapist actively stimulates or seeks to modify energy patterns, having identified an imbalance.
A common mistake for the novice therapist is to 'overdo it': it's tempting to give as much healing as possible, but this generally puts the patient out of balance and that can be very painful or scary (or both!). It's much better to gently address imbalances bit by bit, rather than too intensely. Or, a treatment can be a mix of the two, and it's very often so; in doubt, less is better than more.
The intention of the therapist is very important in the therapeutic relationship and the energetic rapport the therapist establishes with the client: there are in fact several ways the therapist can 'direct' the treatment, and that's the reason why the very same technique can differ greatly from person to person. It's down to the skill and sensitivity of the reflexologist to understand what the client's underlying energy patterns are 'telling' and what they require.
The mental, emotional and spiritual bodies are entwined, so whatever affects one part (positively or negatively) will have repercussions on the whole. So, for example, there is a client who has low energy: as a reflexology and Reiki therapist I would do what in 'jargon' is described as 'bringing up the energy'. The client is low in energy, so the energy needs to be lifted. After investigating further on the possible causes, I would then address the solar plexus and stimulate that at length: what is most likely to happen is that the person will relax completely, 'letting go' of whatever is holding them back. Reiki-wise, I would work 'upwards', because the energy needs to be lifted; but I would work from head to feet if the energy needs 'calming down'. In stimulating the solar plexus area, energy is released in the 'power house' area of our body: it is believed that, energetically, that's where the 'soul' resides. So if your soul has been 'stolen', for any reason (trauma, negative energy, self-attack etc.), energy work in this area will gently change the existing energy patterns and bring gradual healing. It's a very subtle process, and it's one of its greatest merits: it's much better to chip gently at negativity and imbalance, rather than overwhelm the individual. Spiritually speaking, body work coupled with the positive intention of the therapist, will help reintegrate naturally and gradually lost parts of the 'soul'.
Tragically, many people chose not to live 'spiritually', not because of being inherently 'bad'; only because their belief system is based on beliefs that are fundamentally wrong. If for example the individual believes a prejudice to be true, that particular individual will act and think according to something that is mistakenly believed to be 'good'. An example is committing murder in the name of a religious belief, or excluding a group of people because of a prejudice (sexism, racial prejudice, sexual orientation prejudice, etc.). As a therapist you can only give a helping hand: a clue that the individual may be ready to accept that help, is that they have sought to receive a treatment from you. They are 'seeking help', although in my experience people do not often know consciously what they need; but the fact that they actively seek a solution to a problem, is a good sign that they have reached the point where it's become clear to them that they want to get better, they want to overcome whatever is dragging them down. A skilled therapist will intuitively know what approach works best: I think this can be learnt through experience through an extent, but it's also about the life path of the healer/therapist and their natural gifts.