The most important requirements for undertaking our Lord's activities are many. To name a few, - One should follow the path of Selfless Love. Whatever/Whenever he/she is undertaking an activity [be it anything] that should be done without any thinking about what that would result for the doer. If there is results awaited for the activity, the activity never holds any importance in the eyes of our lord.
When we do anything, we should do it with the utmost devotion, love, and obedience. We should feel that we are not the doers, the doer is our Sri Sai himself. After all, we are nothing but mere instruments in his hands for His work to get accomplished. We should treat the activity recipient as though they are our own.
To whom we serve.... To whom we deliver our seva/activity, we should see our Lord in him / her. Sai has given a wonderful instance about this to Mrs. Tarkhand in the Shri Sai Satcharitra. When Mrs. Tarkhand fed the hungry dog with a piece of bread, the dog relished the food. When she met Sri Sai, Sri Sai said that it was He himself who had come in that form. The food that the dog ate appeased His hunger and He was still belching with the great food. He said, He will be in all the forms may it be, cow, flies, dog, etc. This was an important lesson to everyone, that Sri Sai will be present in everyone and everything. When we deliver our seva or activity, we should always think that we are doing it for our own Sri Sai.
Take the best for the seva/activity. When we do an activity, we have to give the best from ourselves. To quote an example, our beloved Lord Sri Sai showed this. A lady used to do Narayana Seva in her town. She used to buy Rs.2 rice for the seva. For the family, there was Rs.5 rice bought. The Rs.2 rice was filled with Stone, and was not very good for anyone to have. When in an interview she was mentioning about the seva she had been doing for such a long time and Sri Sai should bless more, her pride was knocked. Sri Sai went inside his room and bought a red bag of rice with Him. He asked her, Is this not the rice you have given me when I visited you?. It was the same bag she had offered Him when Sri Sai visited her seva in an unrecognizable form. This is indeed a lesson to everyone, that whenever we do His work, we have to deliver the best of the best.
sri shirdi sai baba is known as an embodiment of the spiritual god himself. when there was a time when people slaughtered each other in the name of religions, he taught acceptance of one god who is worshiped by various people in different names.