From Jimmy Nolen’s chicken scratching to Prince’s slick pop-rock rhythms, 16th-note strumming is a key funk technique. Strum down-updown-up and count ‘1 e & a’ to keep time.
Sparse sounding single-note riffs are common in funk, helping knit the groove together. Try picking hard enough that the string snaps back onto the frets. A compressor pedal helps those notes pop!