Plan in advance. Rather than try to throw everything into a single suitcase the day before your trip, put some thought and consideration into the climate of the area you are traveling to, the activities you will be participating in and the specific clothes, shoes and accessories you will need during each day of your trip.
Select your outfits based on the activities planned for each day and lay them all out, complete with undergarments, shoes and accessories. Look for ways to "re-purpose" some wardrobe items such as wearing the same pair of shoes with multiple outfits or pairing a versatile neutral sweater with more than one change of clothing.
Chose the right suitcase. If you will be restricted to a certain size or weight by an airline, or if you simply have a limited amount of space in a vehicle, make sure the suitcase you select will meet all pre-established requirements.
Open your suitcase and lay it next to the outfits you have selected. Does it look like everything will fit? You may have to pare down some of your items. If you are planning to purchase souvenirs on your trip, leave a little extra room for packing those for your return trip.
Lay pants, dresses and skirts lengthwise in the suitcase so the ends stick out. Lay clothing with a tendency to wrinkle on top of those.
Roll clothing items made from knit fabrics --- along with t-shirts and other less wrinkly items --- on the next layer.
Put socks and underwear inside of your shoes and pack them along the sides of your suitcase. Also, use the sides of your suitcase for packing belts and accessories, which should be secured in a make-up bag.
Fold the legs and arms of the clothing items on the bottom layer over the top of the other layers. Place bagged toiletry supplies on top of the final layer, taking care that liquids are fully sealed.
Close your suitcase to ensure everything fits, and you're ready to go!
