When you read the Model of the prayer that Jesus gave usyou can actually find out that it is exactly what most are especting (from God, for / from others and for / from ourselves)
Whatever you feel, expect is a prayer (our spirit talks to God - that's the most sincere prayer whatever your spirit is asking good or bad - in knowing or not "it" being good or bad).
Now of course you can get into a religious way to do it (but God/Christ already knows what's our spirit wants exactly)
To be more specific :
Without really thinking about it Believer and unbeliever are praying since their feelings are involved