Find a script and just goof off with it. Teaching takes a while, trial and error works better (for me at least) When you get errors google them to figure out the cure.
well go to "http://www.learnphpfree.com/lesson-1- -welcome-to-php-vt23.html" to start off. After that, I recommend getting an ebook/book to learn more.
I recommend downloading the php manual from php.net, looking over the basics through the manual, and then buying a decent beginners book to php. Any issues you come up with can be solved by googling or posting here on DP.
what is your background? do u know any other programming language? r u familiar with html & css? r u familiar with client side scripting like JS ?
i dont know any php i only know basic html like links pics bold underline ect i got 70%on the w3schools htmk test