Once you are holding xBOMB, head over to the bim.money xBOMB pool and add your collateral. To borrow zero BIM do not enter anything in the "BORROW BIM" section.
Another viable strategy is to follow the above steps and then borrow a small percentage of BIM, for example 25%. If you previously borrowed more than 25%, this will decrease your liquidation price to a more comfortable level.
The other method to avoid liquidation is to simply repay some/all of your BIM.