There are some formatting problems with that web page. Try these commands instead:
Set up the path and port variables:
export PATH=~/perforce:$PATH
export P4PORT=1666
Set executable bits on p4d and p4 and start p4d in its default configuration
cd ~/perforce
chmod a+x p4d
p4d -d
chmod a+x p4
Create a test directory for your workspace and initialize the client
mkdir ~/myws
cd ~/myws
p4 client myws
I think they accidentally reformatted the page, so the line breaks were missing.