Bal-Seva of Shri Krishna (God Vishnu) is one of the best way to show bhakti-bhav (devotion) with genuinely taking care (seva-bhav) of the baby form of God. It is most magical way to show your love and affection towards the Divine Energy, as you can really enrich the care with your feelings and dedication in every step of the way.
In Bal-Seva, one has to wake-up, dress (vaga), feed (prasadam), play and put asleep (nindra) Bal-Krishnaji. You are pretty much in-charge of exact times for these all activities in your own format.
In Shivshaktiji’s quote – “The of Spiritual life essence for any devotee is to perform Dhyaan of Shakti, Puja of Shivji and Seva of Shri Bal-Krishna”. A perfect combination to obtain unlimited divine grace and unimaginable Blissfulness. And these righteous processes is the best way to show love and dedication to the Divine Energy.