Well, seems like you just need to study a lot of animation and have a good rig, maybe a mix with curves to get the motion done. There isn’t really much to say, it’s all very manual work and eye, you need to have animating knowledge. I guess we could point you to Wayne’s and Phil’s animation and rigging courses?
https://cgcookie.com/courses/spider-animate-in-blender-easy
https://cgcookie.com/courses/core-fundamentals-of-rigging-blender
https://cgcookie.com/courses/core-fundamentals-of-animation-in-blender
https://cgcookie.com/courses/rig-blender-s-character-rigging-playbook
https://cgcookie.com/courses/animation-bootcamp
