A lehenga is three garments pretending to be one: the skirt, the blouse, and the dupatta drape. The skirt only needs a few numbers, but each one has a trap in it.
Use a soft tape over thin clothing. Give body measurements only; the tailor adds ease for the style you choose.
Scan yourself with your phone camera on Silai: about 2 minutes, free, no tape and no second person. You get every measurement on this page, saved as your naap for any tailor on the platform, in any city or country.
Tied at the lower waist and worn with mid heels, most 5'4" (163 cm) frames need about 102 to 106 cm. The reliable way is to measure yourself from tying point to floor in the shoes you will wear.
The waist can usually go in or out a few centimetres. Length is the hard one: shortening from the hem eats the border, and lengthening is rarely possible. Get the length right first.
The circumference of the hem, a style choice rather than a body measurement. More kalis or panels give more flare and more twirl.
Saree blouse measurements · Kurta and kurti measurements · Salwar kameez measurements · Gown and anarkali measurements · What measurements does a tailor need?