The first thing you should do when you need to pack for a vacation is make a list.  Think of your daily grooming routine and note everything that you need to take with you.  Also, consider how many days you will be gone and note the appropriate amount of clothes, underclothes, etc. that will be necessary.  Each person that travels will need a separate list, but you should be able to compare them and compile several elements in the personal grooming categories.

Buy or borrow suitcases.  You should have at least two bags.  A larger suitcase is necessary for your clothing and hygiene products while you should always keep a smaller bag that you can carry with the more valuable belongings you are taking, including your documentation. 

Make sure to pack the appropriate amount of clothes for the length of your trip.  Remember all layers and situations.  Do not forget a bathing suit, if necessary, or pajamas.  Remember to pack the necessary accessories, such as a tie or earrings.  Packing a needle and thread may be useful to avoid unnecessary stress that could result from an unfortunate tear in your clothing.

Pack your grooming and hygiene necessities.  Although you can purchase shampoo, conditioner, razors, deodorant, a brush, sun block and q-tips in most locales, the prices are usually inflated in tourist areas and hotels.  Also, if you use a particular brand, it might not be as readily available in other locations.

Do not forget to be prepared.  Even if you are going somewhere warm, taking a jacket is a good idea because nights may get cold. 

Pack all necessary medicines and put together a first aid kit with bandages and aspirin.

Do not forget the accessories. Modern society has many electronics that people tend to travel with.  If you plan to take your digital camera, cell phone or music device, make sure that you have the necessary accessories.  Any of the aforementioned will be useless if you forget the charger, batteries or manual.

 Do not forget recreational activities.  These could include reading materials, music, candles or sporting equipment.  Likewise, if you smoke cigarettes, you may want to include the amount that you anticipate smoking because they tend to be more expensive in different areas and it is often impossible to find certain brands.

Pack necessary documentation.  You will need your travel documents, insurance cards and identification.  It may also be useful to take a list of emergency phone numbers and addresses.  You should also make sure that you have a sufficient supply of cash or travelers' checks.  Additionally, it is wise to carry a credit or debit card for emergency funds.

Place your travel documents and identification in an easy to reach, safe place.  It is especially convenient to put them in a zippered compartment on the outside of your carried back.  This ensures that you will not lose them but provides easy access.