Let me first describe my initial routine, and how it spiraled into me quitting anki entirely. Then my current routine which actually works.
When I started learning Korean, I grabbed anki + Evita's 5k words deck. It's a pretty good deck, but lacks sentence samples. I use the mac osx app at home and the ios app on the go. The ios app is $20 but you can use ankiweb.net to do reviews. The android app is free.
For about six months I did anki just about every day, @ 20 new words/day. This took me anywhere from 30-50 minutes depending on my focus. It always took longer if I missed the previous day, because then I would have to re-do the newly-learned words (1-3 days interval). I had to commute on the bus every day so I was able to easily knock out anki as I just forced myself not to use reddit/HN before doing anki.
However after a certain point I had missed a few days, which made the next anki cycle take longer. It was frustrating, and caused me to miss more days.. Eventually I had so many reviews piled up that I didn't even want to open anki at all.
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How did I fix this? For starters, I used a custom session to knock out all the 400+ backed up review cards at once. It took me a good 3 or 4 hours. Next, I reduced the new daily card limit to 10. I think 20 is unsustainable unless you are consistently studying at least 3-4 hours daily. Since I work and also study Korean grammar/resources it was just too much.
Next, I changed the default system from "mixed review" (new cards + review cards) to "review cards first". This way even if I don't have the time or energy, I can still knock out the daily reviews. If done right it can be as short as 5-10 minutes depending on how many reviews you have for that day. It's not ideal but still far better than you backsliding on your learned words.
For beginners you can use premade decks, just make sure they have good reviews, and are ordered so you learn words like "mom" before you learn "diplomacy". If you google anki + $language deck, there are recommended ones on reddit usually. That's how I found the core2k japanese deck, which may be the best I've used so far.
However after that point you really ought to be making your own decks. Through your study you should be finding new words; write these down and add them to anki but be prudent about it. I made the mistake of learning advanced and niche words before learning "circle" and "foggy", which are way more useful to know. Also, add sample sentences. It's not really helpful to know a word but not the context when it is used.
In anki you can add custom fields for card types, so I added ones for grammar type, notes, sample sentences, and hanja. I also made a color card with custom html and css styling to let me practice memorizing color words. You can look into cloze deletion cards, I have heard they're good but have not used them myself.
Tip: You can bulk import anki cards from csv files. I maintain a spreadsheet and add them every so often.
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Nowadays I use 2 decks: my personal korean one @ 5 words/day and nihongoshark kanji @ 20 kanji/day. The reason being I am focusing more on memorizing 2k kanji right now. I do the korean one while taking the bus home from work and then I do the kanji one right away at home or at a cafe.
Hopefully this clarified things, otherwise let me know if you have any questions. Anki's manual documentation is actually very good so I recommend reading that.