Family members did combination of some reading of the booklet and practice tests. In my opinion, the ones who read the booklet and then practice tests did far better (the other one sort-of read the booklet).
Dates and to a lesser degree names: they mostly aren't trying to trip you up. Dates on a multiple choice will generally be grouped - two completely ridiculous answers, one that might kind-of be plausible if you were confused between two topics, and one that's obviously right.
In other words: they won't ask 'what year did Nunavut become a territory' with answers 1997,1998,1999, 2002. It will offer eg 1868, 1905, 1999, and 2017 - so if you're aware that Nunavut was created 'recently but not yesterday', it's easy.
Names are a little trickier but somewhat similar - and they don't usually ask about really obscure people. Logical groupings and knowledge of the overall history is more important than memorizing a bunch of facts and dates.
Again, they're really not trying to trick you. With a good read and a little bit of practice, you'll probably get above 15 (the min required) on the first try. Typically there are 2-3 more difficult/obscure tests out of the 20, on a bad day, you might not pass the first time.
Those with worse English may have a bit more difficulty though. Make sure to use practice tests that correctly identify your province, i.e. the test is different in Ontario than in BC.