Automate Rota

Hi All, I have no idea where to start with this so any pointers will be hugely appreciated. I have been asked to help automate a personnel rota where a client has a number of permanent staff allocated to them and then to achieve the required presence additional relief staff may be allocated. For instance, Lima 94 has a requirement for four day staff Monday to Friday and three day staff Saturday & Sunday. In addition they require three night staff Monday to Sunday. There are 5 permanent staff allocated and the other slots are filled by relievers. There are four shift types, a) Days (five days on, two days off,Monday to Friday) : Extended Days(Five days on, two days off, any days, c) Both Shift, (three days on, three nights on, three days off, d) Permanent nights, (nine night on, eight days off). At the moment this is all done manually in Excel but it takes forever