Look somebody up and down
Definition 1 of 2
Pro Tip 1/3Judgmental Tone
This phrase can imply a critical assessment of someone's appearance or style. 
As soon as he walked in, the group looked him up and down, whispering disapprovingly among themselves.
Pro Tip 2/3Non-Verbal Opinion
Using this phrase shows an opinion is being formed without saying anything out loud. 
The fashion designer looked her up and down, pondering her model potential.
Pro Tip 3/3Possible Discomfort
Someone might feel uncomfortable or embarrassed when looked up and down. 
At the interview, the panel looked her up and down, making her nervous.