Blow Job Tips

Okay ladies I’ve been dating the same guy for 5 years and we’ve been getting down and dirty for 4.5 of those years. While we usually tear it up in the bedroom, I feel like I need to switch up/improve my bj game. He hasn’t said anything to me about it, but I’m just to the point where I feel like it’s boring for both of us. Any tips/pointers/fail-proof methods? He’s the only guy I’ve ever been with too so my experience is limited. Please help me 😩