Here are quick tips to avoid forgetting or losing items:
1. Buy or dedicate a purse or bag that's only for travel, and keep it ready to go. I have a purse that I use only when I travel, because I don't like my nice purses getting beat up on planes. If you always keep a brush, toothbrush, and other "why did I forget that" items in it, you're always ready when you pack.
2. Pack your toiletries bag the night before and put them in your dedicated purse or travel bag. The night before I leave, I make sure my travel purse is ready to go, even if the rest of my packing isn't quite done yet. I could walk out of my house without my luggage (or conversely, if my luggage is checked and takes an unscheduled detour...) and still be able to survive.
3. Don't pack your whole make up kit. You need the very basics in make up when you're traveling: mascara, lip gloss, powder and a good moisturizer are the only unique things you need in your make up arsenal. Everything else you pack for your glamor-gal looks can be used dually. Pack a dual-tone blush that you can use for eyeshadow, or pack an eyeshadow pack that has a pinkish hue to brighten your cheeks. Skip a pencil and use a liner brush, water, and your darkest eye shadow as your liner or brow filler. You can also take one intense lip color and mix it with lip balm - I love Burt's Bees - to adjust the shade of your lip color depending on the time of day. And if you want makeup that stays put all day, consider getting She Laq from Benefit Cosmetics. Apply it to anything on your face, and it stays put. It's brilliant.
4. Don't pack wall chargers for your cellphones if they can also be charged by USB cord. My blackberries can be charged via USB, and I'm much less likely to leave that cord behind if it's attached to my laptop when I pack up.
5. If you only have wall chargers for your cellphones, buy two. Before you unplug your phone from the charger, unplug it from the wall first and immediately put the wall charger in your bag.
6. If you've forgotten your laptop charger and it's critical, look for an office supply store when you land. This isn't a situation where you can ask the front desk - laptop chargers, if they're not compatible, can damage your battery. So consider going without using your computer if you can't find one. If it's critical that you have one, find a universal one that has appropriate connectors and adjustable voltage.