What is the Sunnah way of viewing a female for marriage?

Answer

For the purposes of marriage it is permissible and advisable to see the woman. She should be with a male mahram (father, brother, uncle) when the man comes to see her. He should see her briefly for a minute or two. Conversation is not allowed.

The purpose of viewing is to ascertain if there is a physical attraction between the couple. If there is no physical attraction at the first viewing, then it is best not to proceed with the contemplated marriage.

Understand well, that the character of the girl or of the boy cannot be ascertained from a brief viewing. The purpose of the viewing is not to ascertain character and compatibility. The parents/seniors of the family should investigate from different sources to ascertain the characters and mannerism of the couple.