How can i solve by completing the square? I know a bit how but i just need some help!

X^2-X-1=0

X^2-X=1

X^2-x/2=1/2

X^2-x/2+(-1/4)^2=1/2+(-1/4)^2

I get lost here can some one help me solve or make any corrections THNX!