WHAT IS ISTIKHARA ?
Istikhara in arabic means taking Allahs help. Whenever one wants to undertake a decision or a matter or anything regarding his life whether it be an important matter or a casual matter, he can (should) pray two raka'ats nawafil prayer and supplicate the below mentioned dua of istikhara after it to seek the help of Allah in his matter/decision.Istikhara cannot be done for haraam or disliked matters in Islam (working in a bank operating on interest, going to a club, having illegal sexual intercourse and etc). Istikhara is only and only allowed for matters which are mubah (allowed) or mustahab (recommended) in Islam concerning either an individual's personal life (property etc) or religious life (marriage, help in Islamic issues).
Always remember : {Does He Who created not know, while He is The Subtle, The Acquainted?} [Quran 67:14]