Try this to make a file hidden:
mv filename .filename (you can also specify a path for the hidden file, but as it is here, it will stay in the same directory)
The line above just moves the file with "mv" command, but renames it with a period at the beggining of its name which will make it hidden.
And to delete all hidden files within a directory:
rm -f -v .*
This will delete all files whose names start with a period i.e. Hidden files.