Born in Rome, Lazio, Cappa left for Abruzzo club Pescara at young age. In 2006–07 season he was the member of Rome's Tor Tre Teste; He was the member of Pescara's Allievi under-17 team in 2009–10 season. From July 2010 to January 2012, he spent 1½ seasons for the under-20 reserve of Pescara. However, he also played for the reserve B in 2010–11 season. Cappa also made his senior debut for the first team on 4 September 2011, against Modena. On 11 January 2012 Cappa left Pescara to Serie D club Teramo, with Riccardo Ragni returned to Pescara as backup keeper; the reserve were played by Salvatore Falso and overage player Francesco Cattenari. Teramo won promotion back to fully professional league in 2012; Pescara also promoted to Serie A in the same time.
Vicenza
On 29 June 2012, second last day of the financial year of "Vicenza Calcio S.p.A." and "Delfino Pescara 1936 S.r.l.", both clubs made swap deals, which saw Elvis Abbruscato for Stefano Giacomelli ; Francesco Caratelli for Filippo Di Pentima and Alessio Bruno for Cappa. Vicenza also made similar deal that saw that swapped Giulio Cavallari for Richard Gabriel Marcone of Siena, both keepers. The swap deals made the clubs also had huge financial benefit as well as in the football field. Cappa signed a 3-year contract. Marcone was immediately left Vicenza in temporary deal, but Cappa remained for Vicenza's third division campaign, along with Nicola Maggio who was on trial. Cappa played once in the friendly. He also received call-up against Empoli in 2012–13 Coppa Italia. However Cappa was a surplus to team after Vicenza re-admitted to Serie B to replace Lecce as well as signing Stefano Fortunato and Achille Coser. Cappa was signed by Chieti on 28 August 2012. In the whole 2012–13 Lega Pro Seconda Divisione, Cappa was the understudy of Ivano Feola, who just 2-year older than Cappa. However Cappa was the first choice of Chieti in the promotion playoffs, which the team was eliminated in the first round. In June 2013 the co-ownership deals between Pescara and Vicenza were renewed despite the relegation of Vicenza.
