In WaniKani to Anki exporter choose any of the exporter options and save the file locally.
Note: The comments at the top of the file define the field header names and these are currently #key;type;character;meaning;image;onyomi;kunyomi;important_reading;kana;level which are the merged fields returned by https://www.wanikani.com/api
Start Anki and choose Tools > Manage Note Types.
Click the Add button, select "Add: Basic" and click Ok. Type in WaniKani for the Note Type Name and click Ok
For each of the field headers above, click Add to create a new field in Anki.

Tools > Study Deck...
click Add and in the New deck name enter WaniKani, and click Ok.
Cancel the Study Deck dialog
On the main page of Anki click the Add button at the top
In the dialog make sure the Type is "WaniKani" and Deck is "WaniKani"
Click the Cards... button
At the bottom of the Card Types for WaniKani window click the More button and click Rename, type WaniKani and click Ok
For Front Template use
<div class="ja {{type}}">
{{#character}}{{character}}{{/character}}
{{#image}}<img src="{{image}}"/>{{/image}}
</div> For Styling use
.card {
font-family: arial;
font-size: 40px;
text-align: center;
color: black;
background-color: white;
}
.ja {
color: #fff;
font-size: 6em;
font-weight: normal;
line-height: 1.6em;
}
.radical {
background-color: #00a0f1;
box-shadow: 0 0 10px rgba(0, 0, 0, 0.25) inset;
text-shadow: 5px 5px 0 #0093dd;
}
.kanji {
background-color: #f100a0;
box-shadow: 0 0 10px rgba(0, 0, 0, 0.25) inset;
text-shadow: 5px 5px 0 #dd0093;
}
.vocabulary {
background-color: #a000f1;
box-shadow: 0 0 10px rgba(0, 0, 0, 0.25) inset;
text-shadow: 5px 5px 0 #9300dd;
}
.small {
margin-top: 2em;
font-size: 0.5em;
} For Back Template use
{{FrontSide}}
<hr id=answer>
{{#kana}}<div class="kana">{{kana}}</div>{{/kana}}
<div class="meaning">{{meaning}}</div>
{{#important_reading}}<div class="important_reading">Important Reading: {{important_reading}}</div>{{/important_reading}}
{{#onyomi}}<div class="onyomin">Onyomi: {{onyomi}}</div>{{/onyomi}}
{{#kunyomi}}<div class="kunyomi">Kunyomi: {{kunyomi}}</div>{{/kunyomi}}
<div class="small">Card type: {{type}}</div> File > Import, select the file, and click Open

Make sure the Type is WaniKani and the Deck is WaniKani
Make sure that import option is set to "Import even if existing note has the same first field"
Since the fields being imported are in the same order as the Note Type previously created there is no need to change the mapping.
Click Import