In pretty much every case the title is a bright blood red color, signifying many things such as anger or violence, but also attraction or lust.
The use of red is because most noir films contain violence as most of the plot, as well as sexual attraction between the femme fatale and anti-hero.
Most of the titles are short, usually 1 or 2 words maximum. For example, Sin City, Mulholland Drive, The Killers.Sin City's title has pretty much every convention of a Noir film, and is a great example.
The color is bright red which symbolizes anger and violence, but it also stands out very well as the background is very dark.
Also, the font is quite thick, but it almost looks like a comic book font. This is great, because it's blocky and slanted, but still interesting as it's different.
The title itself is also only 2 words, but is still very impacting because SIN is a very iconic word that relates to most things bad and evil.
