Stroke order is the order and direction in which the different lines and that make up a kanji need to be drawn. Sites like jisho.org have guides showing you how to draw a kanji in the correct stroke order. For example, for the kanji 日
Stroke order is particularly critical if you are interested in writing kanji by hand. Nowadays however, most writing is done by typing in computers and the like, so it is not really necessary. Knowing stroke order, however, has a couple interesting advantages:
- It can help you find the meaning of a kanji you don’t know yet, and that you found in printed paper and thus cannot easily copy paste. Many sites (like jisho.org or sljfaq ) allow you to draw a kanji and then the site attempts to recognize it. They are way more accurate if you use the proper stroke order.
- It makes it somewhat easier to recognize a kanji when it is presented to you in a different font.
I personally find this advantages are marginal, so my suggestion is to follow Leebo’s advice and check Tofugu’s guide and use their rules of thumb, and not worry too much about stroke order.
Leebo already mentioned that there’s no issue with starting right away, and the WaniKani team suggests starting after level 10. My advice is not to start later than level 10 . The sooner you understand grammar, the sooner you can start attempting to actually read native material; and I feel this is very important to actually make the kanji you learn in WK stick to your memory. WK’s SRS-based methodology is great, but no exposure to the kanji in the wild will make it a lot harder to retain properly.
There’s been cases of people working hard on going through WK very fast but neglecting their grammar, and eventually find that even though they recognize a lot of kanji in a japanese text, they can’t really understand it (I am one of those >.<)
I think the first three free levels will give you a clear idea of WK’s methodology and help you decide whether you think it is properly working for you or not. WK is definitely not for everyone; it is more of a one-size-fits-most than a one-size-fits-all thing.
Reviews and lessons piling up can definitely be problematic and many people burn out after a while because WK can be very unforgiving in that regard; you can’t easily take breaks (WK does offer an option for “vacation mode”, but that has a few problems on its own, mainly that you won’t get any reviews but your brain will start forgetting stuff, specially the items you learned recently)
For this reason pacing is very important. Proper pacing is not really that difficulty: it boils down to how many lessons you decide you want to take per day. People trying to go very fast will take 20-25 lessons per day (or plain crazy ones will just take all lessons as soon as they are available; this tends to create huge review piles that can be discouraging though), while people taking it very calmly will do 3-5 lessons per day. The key here is to do as many as you feel comfortable, which will take a bit of experimenting. If you feel you have too many reviews per day, then reduce the number of lessons you take, and reviews will start being less overwhelming.
Aside from the list of resources in the previous post, I’d like to mention that WaniKani’s main focus is kanji. While WK will teach you vocabulary, this vocabulary is more like an added bonus - a way to re-inforce the kanji you are learning. WK will teach you a lot of useful vocabulary, but it won’t cover a huge amount of common words.
This means that you will need other resources to fill the vocabulary gaps you will find when attempting to actually read japanese material.