The eggs and oil should be at the same temperature and that not too cold. In summer it is easier to make a good mayonnaise beginning with 2 egg yolks.
Remove every trace of egg white from the yolks. Put the yolks in a thick basin which will stand steady in spite of vigorous beating. Add to the egg yolks the pepper, salt and mustard to taste. Drop by drop add the olive oil, beating or wh