Regardless if using an OCXO, TCXO or XO, every measure should be taken to mitigate the effects of temperature and air flow on the oscillator. Below are some considerations:
1. Try to place the oscillator where air flow is reduced by obstructions, such as placing the oscillator behind taller components or mechanical parts.
2. Keep the oscillator away from heat sources. Avoid solid copper planes (power, ground) on layers below the oscillator; as more copper increases the heat transfer exchange.
3. A plastic or metal case may be available from the oscillator manufacturer, or can be custom designed, to fit over top of the oscillator to provide a layer of insulation from sudden temperature changes.