Once you are in touch with the Vocations Director, you will have a series of chats with him that helps him to get to know you as a person: your journey so far, and the things that have inspired you to get in touch. It is also likely that he will link you into a group of like minded people with meetings which are a mix of some input about Priesthood, some sharing and some time for personal prayer.
The Vocations Director will also suggest some books and articles for personal reading, and will help with any questions you have. It may be that this is in conjunction with other Priests, or Religious Brothers or Sisters, or lay chaplains, depending on your existing contacts – with your Parish Priest or University Chaplain, for example, or with a religious community.
With a Diocesan Vocations Director, the initial focus will be on Vocation in general: are you called to Priesthood, to married life, to single life, or to life as a Religious Brother or Sister? As things become clearer, there may be other people who you are directed towards; ultimately the Vocations Director will have the greatest expertise within the Diocesan priesthood, and if your vocation lies elsewhere then he will point you in the most helpful places for you.
Depending on your own journey and circumstances – it may be that there is a College or University course that it is wise for you to finish, or work commitments to complete which affect the timing of things, in addition to your own personal discernment – then after some months or years journeying in this way, and if it is evident that you are called to the Diocesan Priesthood, it would become time to submit a formal application to the Bishop.