Ibn 'Abbaas (R.A) says that Rasulullah (S.A.W) used to say:
"Choose white clothing, as it is the best clothing. White clothing should be worn whilst living, and the dead should be buried in white. (DE)
English reference (DE): Book 8, Hadith 65 (DE)
Arabic reference (DE): Book 8, Hadith 67 (DE)