Use truecrypt or its successor. Use the plausible deniability option to have 2 encrypted partitions so you can provide a password when requested that opens a pa

Use truecrypt or its successor. Use the plausible deniability option to have 2 encrypted partitions so you can provide a password when requested that opens a partition you don't mind law enforcement accessing. You must also follow the general rules of use to ensure that it looks like a valid partition to anyone who you are trying to convince.