What I have found to work for me is to actually type the code into your text editor from the book examples instead of copying/pasting from the downloadable code. Yes...it's long! But what ends up happening is that a lot of the code throughout the book repeats itself, so you end up typing the same thing over and over and over again. Well, after a while, it gets imprinted in your brain and you'll soon be needing an escape from it. Trust me, after a while, you won't forget the basics. Furthermore, by typing it in, you'll inevitably make typographical errors, thus forcing you to debug your own code and finding the errors. This also forces you to truely understand what is happening with the code, because you have to hunt and peck each line as to where the error is.
Also, I've tried to study a little bit each day, whether it is typing in code, reading the book and understanding the code, customizing certain features of the code, or reading various website message boards regarding PHP. Ultimately, every little bit helps build the foundation.
P.S. Another aid to learning was the use of VIM as my text editor. When you tell the application that the document type is PHP, then it ends up colorizing the code for you and as you're typing it in, you can spot almost immediately if you forgot a quote or something. Check out http://www.vim.org/
for more info.