Also here is a list of all known lightsaber colour crystals As well as their owners (if known). And some background! I myself would use Green and blue and make an aqua like Galen Marek did. That or Cyan.
For millennia, the Jedi Order lit lightsabers in every color and hue imaginable. However, following the Battle of Ruusan, the hues of most available crystals had been limited to either blue or green. Lightsaber color crystals could also be compressed, resulting in a pulsating blade, or they could be unstable, resulting in a core which swirled and sparkled.
Lightsaber crystals of different hues could also be used in the same lightsaber to make a new blade color; for example, Galen Marek used Rahm Kota's green crystal along with his father's blue crystal to create an aqua blade.
The following is a list of all known blade colors.
Acid Yellow (Anja Gallandro's lightsaber)
Amber
Amethyst (such as Mace Windu's lightsaber)
Aqua (Galen Marek's modified lightsaber)
Azure (Nikkos Tyris's lightsaber)
Blue (traditional Jedi lightsaber color)
Black
Blue-core (white with blue core)
Blue, w/ black core
Blue, w/ cyan core
Blue, Dark (such as Anakin Skywalker's lightsaber, Kenobi's Legacy)
Blue, Icy (Permafrost crystal)
Blue, Jade
Bright Gold
Bronze (Lowbacca's lightsaber and Freedon Nadd)
Bronze w/ yellow core (Heart of the Guardian)
Brown (Bnar's Sacrifice)
Burgundy (Solimon Dambrizi's lightsaber)
Carmine (Bane's Heart)
Clear (Barab Ingot)
Cobalt (Saesee Tiin's lightsaber)
Crimson (Adi Gallia's lightsaber in 32 BBY)
Cyan (such as Meetra Surik's lightsaber)
Cyan w/ silvery glow (Mantle of the Force)
Electric Blue
Emerald (such as Jacen Solo's lightsaber before his ascension to Sith Lord)
Gold (such as Qu Rahn's lightsaber)
Gray
Green (Luke Skywalker's lightsaber)
Green, Dark
Green, Jade
Green, Light
Green, Sage (Rahm Kota's lightsaber)
Green, Lime
Green, Mint
Green w/ black core (Dahgee crystal)
Indigo
Magenta (such as Mara Jade's first lightsaber)
Orange (such as Kyle Katarn's in 10 ABY or the Mandalorian Knights)
Orange w/ black core
Orange w/ yellow core
Orange, Hot
Orange, Burnt
Pearl White (Krayt dragon pearl, Wisdom crystal)
Pewter (Raynar Thul's lightsaber)
Pink (Lambent)
Pink-Purple
Purple (Mace Windu's lightsaber)
Purple w/ black core
Red (Darth Andeddu's Crystal, generic Sith/Dark Jedi lightsaber)
Red, w/ black core
Red w/ orange core
Red, Blood (Qixoni crystal)
Red, Dark
Red, Light
Sapphire (Yarael Poof's lightsaber)
Scarlet (Depa Billaba's lightsaber)
Sickly green (Jedgar's lightsaber)
Silver (Durindfire (crystal))
Silvery-blue (Toro Irana's lightsaber)
Silvery-green (Viridian crystal)
Teal (Sunrider's Destiny)
Transparent Blue (Pix's lightsaber)
Turquoise (Tenel Ka Djo's lightsaber)
Violet (such as Anakin Solo's, Kyp Durron's, and Jaina Solo's lightsabers
Violet, Dark
Violet, Light
Violet w/ Black Core
Viridian
White (Imperial Knights, Star Wars: The Old Republic)
White-black (white with black core)
Yellow (Impact Crystal from the Force Unleashed II Collectors Edition, and Yun's lightsaber)
Yellow, Dark
Yellow, Light
Yellow-White (Nelani Dinn's lightsaber)
Yellowish-green (such as Ahsoka Tano's Shoto)
Yellowish-orange
Yellow w/ Black Core