If the steady lights aren’t steady and the blinky lights aren’t blinking, the only thing I know to do is call my ISP.
Well, except for that time my wifi router died; I figured out that by using the cord from the modem to the router as an umbilicus to my laptop, I had connectivity again, until I bought a new router. (And it took José at my ISP to get the computer and router to talk – though I think I’d have eventually figured it myself. And it took Philip at Canon a VERY long time to figure out how to get my printer to talk to the new router; I almost despaired of that and went and bought a USB cable).
When my cable modem doesn’t do right, I pull the power cable out of the back, wait a little bit, and plug it back in. If that doesn’t work — at 11:xx p.m. — I ignore it until morning. Mrs. McG and I can putter on the intarwebz with our phones in the meantime, if we must.