Depending on your user role, add a batch payment to bundle multiple bills into one payment transaction. Then export the payment to pay it from your bank account.
For more details, see: help.xero.com/us/MakeBatch
If you're using the NZ/AU/UK or Global Edition of Xero, the process is slightly different - so please watch this video instead: vimeo.com/177988102.
Create a Batch Payment in Xero - US from Xero on Vimeo.