Your picture implies you're an electric player.
First rule: Play less.
Second rule: Never forget first rule.
Most new bluegrass bass players (and I was one) get a little experience under their fingers and they start throwing in all kinds of stuff: walk-ups, walk-downs, grace notes, 16th-note arpeggios, you name it. Stop it! Play IN TWO. When you are TRULY solid in two, THEN you can add a few little things in four - like, once a tune, maybe. You're half the rhythm section and if there's not a mandolin player, you're 7/8 of it (guitar players are supposed to "chunk" on two and for also, but most of them try to do all that hippie strumming instead). As soon as you move out of playing a BIG SOLID NOTE on 1 and 3, the whole thing can fall apart.
Players on electric or players coming from electric are particularly prone to this, because it's so easy to play a ton of notes on the electric.
Especially avoid the constant walk-up and walk-down at chord changes. Yeah, you can do it occasionally, but the way most newbie bluegrass players do it, it's like screaming "CHORD CHANGE NOW!!!!!!" every four bars, in perpetuity. Hey, we know the tune already, you don't have to hit us all over the head with it!