I found this one took more work than most of the others. It's not that it's difficult - it isn't - just that there's a lot of new material to learn.
When you learn you Highway Code, you already know most of it, having experienced roads (as a pedistrian, or a passenger, or cyclist) for most of your life. But with Air Law, I had to learn everything completely from scratch.
I did most of the work in one week - took the week off work, flew most days, and worked on Air Law for an hour or two a day when not flying. It can certainly be done without paying for ground school, though, especially if cash is tight.
Biggest piece of advice I have (and this applies for all exams) is to learn everything, then do the PPL Confuser test. If you get a good mark in the Confuser, you know you can do it for real without having to worry. If not, go away and learn some more. (Watch out for one or two wrong answers in the Confuser, though!)
Good luck!
FFF
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