Databsae design

It is a quite complex subject and question is very generic. You will need to google this question and you will know from the results you get. 

 

You will probably have to follow several articles available online at places such as sqlservercentral.com then there are dba such as Brent Ozar who write several blogs on the subject.

 

There are parameters such as security, disk space, logging, back-up restore process, etc. which are all subjects by themselves.