Not a proficient musician by any stretch of metrics/imagination. But adding onto learning new pieces, what worked for me personally is hearing the parts in the

Not a proficient musician by any stretch of metrics/imagination. But adding onto learning new pieces, what worked for me personally is hearing the parts in the original recording, and singing the melody with my voice if it's melody or vocalizing and tapping the rhythm with my whole body (foot and spine engaged) if it's a rhythm pattern. That way, when I am playing my instrument when that problematic measure comes, I'll simultaneously sing out the melody or tap out the rhythm; and even if my technique is poor and can't play the fast series 16th notes, I'll hear the correct melody/rhythm/gestalt in my head and what I am off by and try again.