When Angel Rangel joined Swansea in 2007 he paid part of the transfer fee himself. The following summer he returned to Spain and helped out in his mother's small supermarket as she recovered from a stroke. If Swansea need a translator for an interview with one of their Spanish players, Rangel steps forward. During Swansea's recent break in Dubai, when punters asked for their picture to be taken with Michu, Rangel was the one holding the camera. Nothing is too much trouble for this man.

And that is before we get to the sandwich run. "I think that went a bit out of proportion," Rangel says, referring to the widespread praise he received after it emerged he had driven around Swansea for an hour, on a bitterly cold Friday night in January, with his wife, Nikki, looking for homeless people to give sandwiches to after they had discovered that the coffee shop they were in was going to throw the food away. They eventually came across a charity shelter in the city, courtesy of some help from Twitter.

"It wasn't as big as some people were saying," Rangel says, shrugging his shoulders. "I just gave a few sandwiches to a charity home. I wasn't driving around Swansea with a truck full of sandwiches. It was just a little gesture. Nothing else. I'm sure there are so many people that do it and they don't get what they deserve, especially those who work 24/7 in the charity homes and help the homeless people. No one talks about them. OK, I'm a footballer and I've done it and it's been in the spotlight but, at the end of the day, I'm a normal person, like everyone."

Rangel epitomises the humility running through a Swansea squad that hope to claim the first major trophy in the club's historyon Sunday, when they take on Bradford in the Capital One Cup final. For Rangel, who signed for Swansea when they were a League One club – Roberto Martínez, the manager at the time, went to Spain to watch a striker only to have his head turned by the opposition right-back playing for Terrassa – winning silverware at Wembley would be another milestone on a remarkable journey. "We've got a great chance to put our names into the club's history," he says. "We'll never get a better opportunity to win a cup final."

Not that he is taking anything for granted. "You cannot underestimate Bradford. I've played in the bottom leagues and I know what it is like when you play against a big club – you give everything and more. I think it's important the motivation of our players is 100%. It's not going to be easy; they've beaten three Premier League clubs. But we have to be realistic and think, if we do our best, we're going to win."

Rangel smiles when asked about how much Swansea has changed as a football club since the day he arrived. "I could write a book, easily," he says. "In the first season I was washing my own training kit, I was bringing my own football boots. We didn't have a training ground. From my point of view it was OK but you couldn't really bring big players because they wouldn't accept that.

"Then we moved to Glamorgan, to a public gym, and got better things but we were still having a shower with random people and things like that, which is not an ideal situation. But we got on with it and we succeeded on the pitch. And then, slowly, we're getting a training ground and a lot of better facilities. If we stay here for a long time we'll get all the rewards of what we've been working for."

Away from football Rangel already has plenty to show for his time in south Wales. Having arrived in Swansea single, he met his wife-to-be in the city five years ago and he sounds totally at home in his adopted country. "I feel Welsh," Rangel says. "I've got three kids and they've been born in Wales. My wife's family is Welsh and we're building a house in Swansea, so I think long-term we are going to be here – it's not only football I'm here for. But I know I've also got Spain as a home and we'll go back every summer to see family and friends."

In Sant Carles de la Ràpita, the small Catalonian town where Rangel grew up, they will be glued to their televisions during the final, although that scene will be played out across Spain. The arrival of Michu, Chico Flores and Pablo Hernández this summer has swelled Swansea's Spanish contingent and also kept Rangel busy. "I've tried to help them. I had experience and they were always grateful to me for what I've done, and you could see straight away on the pitch they were settled and they could perform without any concerns. They always say thanks to me."

Michael Laudrup is another with strong Spanish connections and, according to Rangel, the Dane has elevated Swansea to another level since taking over as manager in the summer. "I think Michael has given the players that motivation that we probably needed, that winning mentality and that resilience that probably we lacked before. We know on the ball we are great footballers. But we needed something else and I think what he has done … we have a lost a bit of possession but we're creating more chances, being more direct and aggressive with the ball."

Rangel hopes those qualities will shine through on a day when 30 family and friends are flying over from Spain to watch the latest chapter in his fairytale story. "Five, six years with the club, from League One to go to the Premier League, establish yourself in the top 10 of the Premier League and be in a cup final, well, it would be impossible to believe it," he says. "Hopefully we can win this final, which would put the club in Europe and would be even more incredible."