The midfielder says the Cottagers underwent major transition last term.
"It was a bit of a transitional year for us, one where there were a few new faces," said Sidwell.
"Obviously there will be more players arriving over the summer, but the main body of the squad will have had that experience of playing together.
"It's important to get those new players in early and get the squad nice and settled ahead of the new campaign. I'm looking forward to seeing who else comes in, as last summer we saw the arrival of some very good players."