Stay up-to-date regarding carry-on items (refer back to 6--TRAVEL INFORMATION to the TSA web site for latest rules).
For liquids in checked bags:
- Pack full bottles when small enough in size to be practical
- Squeeze as much air out of partially-full bottles as possible to prevent expansion of air, causing leakage of the liquid.
- Pack all liquid-containing bottles in a zip-lock bag (1 sandwich-sized bag is allowed in carry-on) in case of leakage. Carry extra zip-lock bags, if possible.
- Refer also to TSA site for materials/chemicals banned from airline travel.