Hare Krishna.
People join the Hare Krishna movement for so many reasons. The same can be said when you consider their form of service. Some people want to cook for Krishna, others want to paint and yet others want to learn the scriptures.
So what do we do, if we feel we have no special talents.
Serving Krishna comes in a multitude of forms, but the best choice is always to start off simple.
If it means serving prasadam, sweeping the temple floor, or cleaning the windows. Otherwise, it is always good to speak to head pujari and they can organise for you.
Obviously with service at home, it is different.
I always use the basic rule of "think of the basics". Simple acts such as reading and hearing about Krishna are sometimes the ebst form of service we can perform, depending on our current circumstances. Whatever you do, just remember to follow your heart, and always aim to satisfy the Lord. Even it means offering 1 sabji, then try to make the sabji to the best of your ability.
Hope I was able to offer some assistance.
Hare Krishna !