Bhagavad Gita 12.10अभ्यासेऽप्यसमर्थोऽसि मत्कर्मपरमो भव।मदर्थमपि कर्माणि कुर्वन् सिद्धिमवाप्स्यसि ॥

Even if thou doest mee actions for My sake without practising Yoga thou shalt attain perfection. Thou shalt first attain purity of mind, then Yoga (concentration and meditation), then knowledge and then ultimately perfection (Moksha or liberation). Serving humanity with Narayana Bhava (feeling that one is serving the Lord in all) is also doing actions for the sake of the Lord. such service should go hand in hand with worship of God and meditation.If you are not able to practise the Yoga of meditation mentioned in verse 8 or the Yoga of constant practice mentioned in verse 9, hear the glorious stories connected with the Lord by attending religious discourses, conducted by the devotees of the Lord, sing Kirtan and the praises of the Lord.Practise the nine kinds of Bhagavata Dharma (the nine modes of devotion). viz., (1) hearing the Lilas (glorious and divine sports) of the Lord (Sravana), (2) singing His Names (Kirtana), (3) constant remembrance of the Lord and constant repetition of His Names or Mantras (Smarana), (4) service of His feet (Padasevana), (5) offering flowers in worship (Archana), (6) doing prostrations to the Lord (Vandana), (7) becoming His servant (Dasya), (8) friendship with Him (Sakhya), and (9) doing total selfsurrender to the Lord (Atmanivedana). (Cf.III.19XI.55)