The gemara implies that whether or not an action is considered hachana depends on whether people will realize that the person is actually preparing. Shouldn't hachana depend on what/why you are doing the action, not on what other people will think?
Albert Hochhauser, Israel
The actions being performed are not "labor" forbidden on Shabbat and do not even have any connection to labor. A person is merely walking and therefore there is no reason for the rabbis to prohibit it unless other people will think that he is preparing to perform a labor prohibited on Shabbat and that will only occur if it is clear that this is his intention. This is why this kind of hachana depends on how others understand it.
However if it is an action and involves tircha (effort) invested specifically for after Shabbos, this would be prohibited irrespective of how others interpret his actions. Therefore a person cannot make his bed for after Shabbat or do other actions which he intends for after Shabbat.
Yoel Domb