Lower your expectations. If you were lucky enough to buy a few years ago,you have made a big capital gain. But the housing market is likely to not only stagnate but move down. That means your house should not be seen as superannuation, and savings have to be built elsewhere.
Drive a hard bargain. Buyers are far more demanding than they were at the peak, and that means if you are selling you have better get the house in order. Stained carpets and leaky roofs will no longer be tolerated by buyers who have seen the demand/supply balance shifting towards them.
Go easy on renovation. Spending a fortune on redoing the kitchen makes sense in a booming housing market. But as the market cools you have to be careful not to overcapitalise the house by spending on huge renovations that the market will not pay for on resale.
Consider renting. The gap between the cost of buying a house and renting one is huge, which is itself a clear sign of values that got out of hand. You can take advantage of this situation by renting your ideal house and transferring money into a savings account for future purchase.
Limit you leverage. Debt makes a lot of sense when interest rates are low and house values are rocketing. As this equation reverses, you have to think about bringing down that mortgage as you can no longer rely on gaining house values to bail you out. That might involve taking savings from elsewhere and paying down the mortgage or, in the case of extremely high debt, moving to a cheaper property.