You need a scope with X-Y mode and a two channel function gen that will give you a basic sign wave and 2nd, 4th, 6th, and 8th harmonics, so a lot of people should be equipped well enough for a little Valentine's Day themed graphing (though this post is late for a bunch of the world...)
X channel:
1MHz, 4Vpp, 180 degree phase
2nd harmonic: 3Vpp
4th harmonic: 0.8Vpp, 180 degree phase
6th harmonic: 0.2Vpp
8th harmonic: 0.1Vpp, 180 degree phase
Y channel:
1MHz, 4.5Vpp, 1V DC offset, 90 degree phase
2nd harmonic: 3.6Vpp, 90 degree phase
4th harmonic: 0.2Vpp, 90 degree phase
6th harmonic: 0.6Vpp, 90 degree phase
8th harmonic: 0.1Vpp, 90 degree phase
The frequency doesn't really matter, as long as your display settings and bandwidth are right on the scope end, 1MHz was just easy and was easy to visualize with pretty default settings on my scope.
I've also got a rambling description and the result in a 1 minute video, here:
http://youtu.be/eTlpzvmM0tU