Even though I had grasped the basic process of how the 3d walk cycle goes, unfortunately, things have been far from straight forward when it came to actually doing it. Initially, my work came along fine, but then I began to experience problems with the autokey and character set. Instead of it predicting what the inbetween frames would be like, it would jump straight to the next key frame without making any inbetween frames at all. I wanted the animation to flow, but this caused a lot of problems for me.
See the highlighted frame just before the keyframe, it has not changed position since the last keyframe.
Here are video footages to illustrate the technical problems I've had.
I even tried to do it frame by frame since autokey doesn't work for me, but this made my animation look very rigid and was very difficult. It made me realise how handy the autokey is, when it can be used however.