USE master
GO
CREATE DATABASE database
ON
( NAME = Empl_dat,
   FILENAME = 'f:',
   SIZE = 10,
   MAXSIZE = 50,
   FILEGROWTH = 5 )
LOG ON
( NAME = 'Sales_log',
   FILENAME = 'g:',
   SIZE = 5MB,
   MAXSIZE = 25MB,
   FILEGROWTH = 5MB )
GO
Just use above query and replace database with your database name and logon sizes as per your requirements.. 

How to create database without specifying its size ?