Git clone - head not pointing to master

Hi,
  I am a Git beginner. Recently i started working on a codebase (that is 
checked in to a git repository) of our client, who is not very aware 
about how git works.
The repository has multiple branches such as

origin/user1 origin/master origin/user2

Now when i take a clone of this repository : git clone <repo-url>, a clone of the repo is created on my machine.

But when i do a : "git branch" it shows

user1 *

which means that the "head" is pointing to the "user1" branch.

The client told me that all the recent code were being merged into the "master" branch and hence the "user1" branch has code which is older than "master" branch.

I had 2 queries :

1. Is it possible to make the "head" of the remote point to "master" 
instead of "user1", so that other members of my team get the latest code 
when they try to clone the repository.
2. Is there any way to safely merge "user1" to "master".