Villa came off the bench and scored a second-half double as Vicente Del Bosque's men wrapped up preparations for the World Cup with a 2-0 victory against El Salvador at FedEx Field.
The World Cup holders were not at their best against the 69th-ranked nation, but Spain's all-time leading scorer Villa said his team is now well placed for their World Cup opener against Group B rivals the Netherlands on June 13 after battling through the heat.
"Today it was difficult because of the weather, it was hot and the condition of the grass," said Villa, who took his international tally to 58 goals in 95 appearances.
"I think the team started off well and finished well. I think we're prepared to start the World Cup on the right foot. This was a positive warm-up, these are the same conditions we'll find in Brazil.
"It was difficult to maintain a good rhythm, you take two sprints and then you need to rest. But it was positive."
Villa started the match on the bench before taking to the field after half-time.
Upon his introduction, Villa was deployed in the middle and out wide to accommodate team-mate Diego Costa, something he said he is happy to do.
"Those who came later could only enjoy this match, I'm happy to have scored two goals, two goals that helped the team," he said.
"I started behind the Costa, then drifted to the wing and finished as the striker. I'm happy because the manager sees me in various positions and that gives me more options."
Villa also conceded penalty taking is Spain's biggest weakness after Cesc Fabregas skied a fourth-minute spot-kick over the crossbar.
'It's a shame (that Cesc missed the penalty), if this team has one weakness, its penalties and I say this because I’ve missed several myself," Villa said.
"I hope he'll have confidence and score the next one."
Spain will also come up against Chile and Australia during the World Cup group stages in Brazil.
