change permitions in user home

[Doug Pollard]

I need to change permissions on some of my user files.   I have the 
command but i need to know how to apply it to an individual file.  Do I 
click on the file and then put in the command.   That dosn't seem to 
work.  Been reading all morning can find ways to change all the files 
but not to single out an individual file.  I have files that everybody 
can write to ,read and exicute and I want to change just those files so 
that I as the owner of them can write to them.
            Thanks Doug