Calling the package a "gift" of "used cosmetics" has always worked for me. 100+ packages in 4 years have all made it to me except 3. 2 were confiscated by USPS before making it to the border and 1 was confiscated by Singapore customs who then forwarded me the empty box LOL.
If it is really liquid-y and makes a sound, add a box of Tic Tacs
