"She said he was planning to do this tattoo a little bit before this happened. It was such an important thing to do. I said, 'Yes, I'll do it'."
Garcia said he arrived about 11.45pm and inked a footprint of one of Kopa's children to go with one he had already had tattooed, along with the names of his twin daughters.
That tattoo took about two hours to complete.
It is understood medical staff delayed switching off life support to allow the tattoo to be finished while Kopa's wife and friends watched.
Garcia said the experience was extremely moving and he was happy to have helped.
"I just felt that this would be such a huge thing for the family, for the kids to grow up and know their whole history. I think that would mean a lot.
"I was thinking [what] if it was a friend of mine or someone from my family."
Garcia, who runs the Artero Tattoo Studio in Birkenhead, refused to accept payment for his work, and hoped the tattoo would help the family's healing process.
Kopa life support was switched off today.
A police spokesman said the serious crash unit was investigating.
Friends of the family have set up a Givealittle Page to help raise money for his wife Calli and their daughters Harper, 5, Zoey, 2, and 8-month-old twins Eden and Charli.
Kopa is described on the Givealittle site as a generous and friendly person who always has a smile on his face.
"Hard working, an incredible friend, and all round amazing person - If you know Daniel then you consider yourself lucky to know one of the good guys.
"Naturally Dann's family is devastated. His family is his world. The burden of how to support his family now lies with Calli and Dann's families."
More than $33,600 had already been raised for the family on Givealittle.