WMTS URL:		Step 1: Type in WMTS URL and Click "Connect";
Layers:		Step 2: Select a WMTS Layer;
TileMatrixSet:		Step 2: Select a WMTS TileMatrix (Tiling Schema);
TileMatrix:		Step 3: You don't need to select, but pay attention to how tile matrix are named e.g. {tileMatrixSet}:{level}, {tileMatrixSet}.{level}, etc; you may need to adjust that in getTileUrl function at the end.
Tile Full Extent:
Supported CRS:
DPI:	0.28mm (90.714 DPI) 96	Step 4: Select 0.28mm (90.714 DPI) for most WMTS UNLESS you're sure it's 96 DPI
Format:	PNG JPG	Step 5: Select tile format
Unit:	Meter Feet Degree	Step 6: Select Map unit;
Axis Order:	Lon/Lat Lat/Lon	Step 7: Adjust lon/lat or lat/lon order of tile origin
TileInfo Object:		Step 10: Click "wmts2tileinfo" to generate ArcGIS JavaScript API code
getTileUrl Function:		You may need to adjust "...&TILEMATRIX=..." in getTileUrl() according to step 3