I am using a Brother HL1850.
When I go to the Print Dialogue in InDesign, I click on the "SETUP" button at the bottom left (under the picture of the page).
This opens a Warning window that you should use InDesign settings to get the best result...ignore this and a 2nd Print Dialogue box should open for your Printer.
Don't change anything except for the Duplex settings. On mine this is under a Tab called "Layout" there I can choose, No Duplex, Duplex turning paper on short side and Duplex turning paper on longside.
Then press PRINT in your printers Dialogue box, then press PRINT in the InDesign printing Dialogue box.
Good Luck!