Devotion as a personal quality is steady, wholehearted love directed toward what we hold highest. It shows in attention, loyalty and small acts repeated over time, more than in dramatic feeling. People who have it often seem calmer and kinder, because their lives are organized around something larger than their own moods. It can be cultivated, and the Gita describes how.
Gita 6.47 says that among all yogis, the one who keeps the mind fixed on Krishna with unwavering faith and lovingly worships Him is considered most perfectly united, so go beyond mechanical practice by cultivating a loving relationship through remembrance, prayer and surrender. Gita 6.30 describes seeing God everywhere and everything in God, so remember the divine presence throughout daily activities and treat every person and situation with reverence. Gita 9.34 invites us to fix the mind, devote ourselves, worship and bow.
Devotion also shapes conduct. Gita 6.31 says the yogi who realizes the divine presence in every being and worships with the vision of oneness remains united with the Divine, so express devotion through kindness, respect and service. Gita 11.55 sums up devoted work, goodwill and detachment, and Gita 11.54 and 8.22 say wholehearted, undivided devotion alone reveals and reaches the Lord. Gita 14.26 says unwavering devotion carries one beyond the gunas, so make it a steady daily practice, not an occasional impulse.