One of the most important principles of being a true believer is to prayer or perform Salaah.

Reasons and benefits for Prayer

But celebrate the praises of thy Lord, and be of those who prostrate themselves in adoration. (15:98)

Prayer strengthens peoples belief.

And serve thy Lord until there come unto thee the Hour that is Certain. (15:99)

Worship God during your entire life on earth up until you die.

“Verily, I am Allah: There is no god but I: So serve thou Me [only], and establish regular prayer for celebrating My praise. (20:14)

To show respect for God Almighty by celebration or commemoration.

Recite what is sent of the Book by inspiration to thee, and establish regular Prayer: for Prayer restrains from shameful and unjust deeds; and remembrance of Allah is the greatest [thing in life] without doubt. And Allah knows the [deeds] that ye do. (29:45)

Prayer protects people from doing evil and harm in this world.

Those who rehearse the Book of Allah, establish regular Prayer, and spend [in Charity] out of what We have provided for them, secretly and openly, hope for a commerce that will never fail: (36:29)

Prayer with charity is the best investment for life after death.

For He will pay them their meed, nay, He will give them [even] more out of His Bounty: for He is Oft-Forgiving, Most Ready to appreciate [service]. (36:30)

And will receive even more reward in the Hereafter.

How to prepare for Prayer

See article on How to perform Wudu