I had a similar issue, and at times I wondered if I had a restriction at all, like what the heck did they remove from me, if not 80% of my stomach!
Just start out with small amounts, less than 1/4C and be sure to continue to get enough protein and sip water all day. Don't worry about eating enough so that you feel it. It's best to just eat just short of feeling full. You may have to experiment with that a bit, everyone feels things a little differently.
You'll get the hang of it about the time you move on to soft foods and then it will be a bit different again....and then again when you start adding regular foods. At ever phase, just start out with smaller amounts and see how you react to it, and then gradually add a bit more if you are comfortable. You'll most likely be eating less than 800 calories a day, so somewhere between 500-800 at this point would probably be the range you'd be consuming.