Start computer at Mac or windows choice at startup by default?

I know you hold down alt to get the choice between mac or windows at start up. Sometimes I forget alt, and have to keep restarting. Is it possible so that by default, when i turn on my comp, it goes to that choice start up page so that I dont need to hold down alt?

Ty in advanced

 

I can. it actually starts up my windows partition automatically. I forget that i should've hold alt so I can choose mac or windows. So I am wondering if I can just go to the screen to CHOOSe by default? This way I wont ever need to hold alt. sometimes i want mac, other times i want windows.