What size stretcher do you start with when stretching ears for first time and which sizes come after?

Standard piercings are 16g, meaning you start at a 14 gauge taper. Change the taper to a plug or a tunnel (at low gauges most are curved barbells though) immediately after.

Always wait at least 2 weeks before stretching.

Same process, start with a taper and go to a tunnel, plug, or barbell.

18 g = 1.0mm

16g = 1.2mm

14g = 1.6mm

12g = 2mm

10g = 2.4mm

8g = 3.2mm

6g = 4mm

4g = 5mm

2g = 6mm

0g = 8mm

00g = 10mm

000g = 11mm

0000g = 12mm.

It goes higher, but I don't recommend it.