I echo everything that Kelly said above. My DD, Katie, struggled to sleep when eating (I struggled to keep her awake). A diaper change was all the activity she could handle, then off to dreamland for her!
To establish some type of routine, just keep it all in the proper order (as much as you can): Eat-Activity-Sleep. And, wake her to eat during the day to keep her on some type of schedule and get the calories in during the daytime; let her sleep as long as possible at night. Tracey says this helps them sort out days and nights.
For nighttime, we use every trick in the book: white noise (rain sounds), paci, lullaby, swaddle, rocking, dim lights. But we do try to get her in the crib awake or drowsy awake. The shush part of pat/shh doesn't work for my DD, so we just have a pat. And, she sleeps on her back and will tense up if I hold her on her side (HATES being on her tummy and she thinks she's going to get rolled over). So, I pat her on her shoulder. I really didn't even think the patting was working until 2 nights ago. It still only works when she's sleepy/drowsy.
I remember Katie sleeping all the time and wondering if that was normal. Yep! And, now I wish she'd nap like that during the day. Usually when she's up she's cranky from not sleeping!