Use your fingernails (flamenco style bassically or your fingers strumming with emphasis on the nails as they travel downward) like Stanley and Victor to get the 'chick' sound then add the wah!----even though I am not using a 'wah', I do a reggae version of 'Lord I Lift your name on High'===you can hear a clip of what I am talking about by going to
http://cdbaby.com/cd/szymanski ---my whole record (The Grace Is In My Bass) is 100% bass guitar! You can hear the 'chick' of the reggae strum I am doing on the bass =my website is
http://web.mac.com/stan_szymanski