After the swap is complete and all channels are opened, everybody should set fees to 0. This will allow for free/cheap re-balancing (see my other post).

Hopefully you are using something like ThunderHub or Ride The Lightning to manage your node.

Select the incoming channel. Set base fee to 0, set Fee rate to 0. Hit apply.

Select the outgoing channel. Set base fee to 0, set Fee rate to 0. Hit apply.

One person in the swap does the rebalance.

Once you are rebalanced you can put the fees back to something sensible like 1 and 50 or 0 and 150.

0 base fee will generate more traffic, you can recoup the cost with a higher fee rate for larger transfer.

Or you can use a small base fee like 1 and a lower fee rate. This should stimulate larger transfers only.