1 Blessed is the man that walketh not in the counsel of the ungodly, nor standeth in the way of sinners, nor sitteth in the seat of the scornful. 2 But his delight is in the law of the LORD; and in his law doth he meditate day and night. 3 And he shall be like a tree planted by the rivers of water, that bringeth forth his fruit in his season; his leaf also shall not wither; and whatsoever he doeth shall prosper. 4 The ungodly are not so: but are like the chaff which the wind driveth away. 5 Therefore the ungodly shall not stand in the judgment, nor sinners in the congregation of the righteous. 6 For the LORD knoweth the way of the righteous: but the way of the ungodly shall perish. Psalms 1:1-6 (KJV)

Basically, the word ‘blessed’ connotes the state of prosperity or happiness that comes when a superior bestows his favor (blessing) on one. Consider these other words found in this Psalm for greater insight.
•    Walketh: "to go, walk, behave."
•    Counsel: “advice, purpose”
•    Standeth: "to stand, station, set up, erect.
•    Sitteth: "to dwell, sit, abide, inhabit, remain.
•    Scornful: to scorn, make mouths at, talk arrogantly
•    Delight:. "Pleasure; delight; desire; request; affair; thing.
•    Law: "law; direction; instruction."
•    Meditate: to moan, growl, utter, muse, mutter, meditate, devise, plot, speak- whisper, musing, murmuring.
•    Fruit:  "fruit; reward; price; earnings; product; result

The Blessed man does not walk under the influence, counsel, advice and purpose of the ungodly, wicked and immoral people. He never sets his ways according to their counsel and so does not live by their convictions. He never sits in the seat of the arrogant talkers and mockers but delights and takes pleasure in another. He seeks advice, direction and seeks to learn from the instruction and wisdom that comes or is derived from God's word such a person will bring forth fruit -good fruit, like a good healthy tree would produce. Not just leaves of beauty but beautiful fruit - the product of their actions. Such fruit that will impact generations to come!

Application: The people (friends) or things I walk with closelywill certainly  influence you.  Evaluate your "friendships" and how they influence your life, e.g. entertainment, habits etc.  What is the product of the choices I make? What changes (or adjustments) do I need to make to ensure I reach the goal of life - to bring God pleasure?