Psalm 145:1-5 (AMP):
1I WILL extol You, my God, O King; and I will bless Your name forever and ever [with grateful, affectionate praise]. 2Every day [with its new reasons] will I bless You [affectionately and gratefully praise You]; yes, I will praise Your name forever and ever. 3Great is the Lord and highly to be praised; and His greatness is [so vast and deep as to be] unsearchable. 4One generation shall laud Your works to another and shall declare Your mighty acts. 5On the glorious splendor of Your majesty and on Your wondrous works I will meditate.
The sub-heading for Psalm 145 says: "[A Psalm] of praise. Of David. David may have written this and I'm sure he sang it, but the reason that this Psalm is included, by God, in His Word, is because this is something that EVERY believer should be doing! Make this Psalm your own personal declaration and expression of praise and worship to Him! Verses 10-12 say this:
10All Your works shall praise You, O Lord, and Your loving ones shall bless You [affectionately and gratefully shall Your saints confess and praise You]! 11They shall speak of the glory of Your kingdom and talk of Your power, 12To make known to the sons of men God's mighty deeds and the glorious majesty of His kingdom.
THAT should be our purpose in whatever we do! What will HE do? Verses 19-20:
19He will fulfill the desires of those who reverently and worshipfully fear Him; He also will hear their cry and will save them. 20The Lord preserves all those who love Him, but all the wicked will He destroy.
So I will do verse 21:
21My mouth shall speak the praise of the Lord; and let all flesh bless (affectionately and gratefully praise) His holy name forever and ever.