My parents didn't entertain much when I was growing up. Generally any gatherings of people were centered around family events: baptisms, first communions, Christmas, Easter, graduations, and my grandparents' birthdays. But since I was near the end of in the birth order of both sides, by the time I was growing up, much of this had occurred (outside of the yearly events).
Nor did I grow up in a family where friends came over frequently for dinners or just to gather. While I realize now how good my mom was at planning for multiple people to sit at her dining room table (that easily sat 12), most of what I learned about entertaining came from trial and error.
I still remember one of the first times I hosted a meal as a newly married person and I asked a friend if she thought it was acceptable if I used placemats instead of a tablecloth. I really didn't know the answer (and I know now it doesn't matter).
I also now know that it's more than serving a group of people a meal and worrying about how good the table looks: it's about the time we spend with people. There is a satisfaction in feeding people but mostly when I look back at the times I've hosted meals or been to the homes of others, it's about the laughter, the conversations, the stories we share.
It's about the spots in the tablecloth that people apologize for when they spill something but I wave off because I know that those spots will tell the future stories each time I pull that tablecloth out.
I don't worry about setting a table when I'm preparing for a gathering. Instead I focus my energy into hoping that we enjoy our time around the table. And that we want to do it again.