A Spanish table is often covered with a white linen embroidered tablecloth. There are several very characteristic motives, like those from Talavera or Lagartera.
This kind of table linen is very durable, often passing from mother to daughter from those times when girls embroidered all their linen. You can buy a new hand embroidered -there are still dedicated shops- but you have to be willing to the price you would for any work of art. They are expensive. Of course, you could embroider your own set; the patterns are geometrical and not very difficult. The alternative is to go for just white linen.
The tablecloth will be immaculate and very well ironed. You also would smell the starch. The napkins will be made of the same cloth and probably also embroidered with the same motives. Again, clean, starched and ironed.
Some fresh flowers will cheer all companions at the table, but any centerpiece should be low, Spaniards love to talk and see each other faces when they eat. You could prepare a fruit arrangement, oranges, lemons, apples, apricots, plum, peaches, cherries and other fruits make an eye-catching arrangement. It is very likely that your Spanish host will present you with such a fruit bowl, for you to choose your favorite, as dessert, if you have been invited to a family dinner.
There are usually three courses, appetizer, main course and dessert and the silverware and plates will be laid accordingly. The food is usually served at the stove or at the head of the table, so one of you clean plates will be replaced by another with food. Few times you will need to help yourself. Spanish are used to eat omelets and most eggs dishes using only a fork and it is perfectly good manners to do so. Ask for an extra knife if you need to, as probably it would not be laid out.