What's the general word for '样‘ in '这样，那样’，‘小样’, ‘怎样', ‘好样的’?
样 means 模样 or 样子 (manner/way; appearance/ look) 

这样 = this way/ like this

那样 = that way/ like that

怎样 = what way/ like what/ how

小样的 = small looking one (mock people for being small minded or undignified)

好样的 = good looking one (use in positive way to praise someone looking good by doing something or use in ironic way to mock someone looking bad by doing something)