localhost, mamp, wordpress, multisite and sub domains

Hi guys,

I am currently working for a client who wants a splash page (Yes yes). From the splash page, the client wishes to be able to enter three different subdomains – lets call them public, privat and center. This means the client want a splashpage example.com, and then three sub-domains with three different navbar menues: public.example.com, private.example.com and center.example.com. I am working from my mac, locally currently using localhost:8888 and so on. I know it can be done, but I have a hard time manuvering in the many terms, like splash page, multisite, and subdomains: Can anybody help me out: Can it be done locally using mamp, or do I need to go live. If the former is the case, how can it be done?

best regards

Ps. I work in zerif