Memorize and practice key phrases that are used on a daily basis. Start with simple greetings, such as "hello," "how are you?," "good evening" and the like, and proceed to practical phrases and questions such as "how much does it cost?," "where is [something]?", and "what time is it?" These phrases are universally useful regardless of the language or country and make foreign travel or conversing with non-English speaking friends much easier.
Learn the alphabet. This is especially important for languages that don't use the Latin alphabet, such as Russian or Arabic. Breaking down those exotic, unfamiliar characters may at first seem daunting, but some letters (as in Russian) are phonetically similar to their English pronunciation. Learning the alphabet will help you at least read foreign languages phonetically even if you may not understand the meaning of the words, and give you added familiarity with the written and spoken language.
Deconstruct the new language's basic grammar structure. Read or listen to sample sentences and get a feel for verb conjugation (based on speaker, gender, and number), placement of indirect objects, direct objects, and pronouns, and general sentence structure. For example, English and Chinese are subject-verb-object while Japanese is subject-object-verb. Such techniques can be done quickly and will help you understand the underlying structure of the language.
Practice quick pronunciation exercises. Write down basic vocabulary words in the new language and their equivalent phonetic English pronunciation. Practice out loud. Challenge yourself with difficult vowels, and begin familiarizing yourself with the sound (and facial movements) required for uttering these unfamiliar words.
Listen to the new language. You can do this as a stand-alone activity or, if you want to maximize your time, play audio clips in the background as you perform other techniques. Listening will expose your ears and mind to the unfamiliar sounds of the new language and supplement other means of study if you do it concurrently.