Center line of wall with alcove for tiling - Tile Advice

[hotnuts21]

Im tiling a walk in shower area and im not sure where to start on the longest wall. It has a bulkhead and alcove at one end which means the wall has 3 lenghts.
190cm, 182cm and 170cm.

Im using 60cm wide tiles but im not sure whether to mark the centerline of the wall from the longest or shortest measurement to work out where to start tiling. I will attach a picture of the wall end in a follow up post.

 

[hotnuts21]

Here is the corner of the wall to show what I mean.