Help creating a work out routine

Hey everyone! I have a gym membership and I think I'm always unmotivated to go to the gym because I haven't made a workout routine. Usually I'll just so and run, do the elliptical, and some weights. Any suggestions on how to create a workout routine to tone and lose some weight?? Open to dieting suggestions as well. I'm a female and I'm 5'7" and 160lbs. Thanks!