These are all fantastic suggestions.
I travel a lot but rarely exclusively by air. Often, air and train combined, and occasionally by car. Sometimes my trips are longer. In that case, I check a bag. My carry on is 19" and sometimes (especially for cold climates or where activities will be varied) I just can't squeeze everything in. Because of the type of travel I do, like Ann, I have different kinds of bags, but I heartily recommend four wheels vs. two if you are going to be outdoors and maneuvering. Four wheels are great for airports but not so much for the more rugged conditions elsewhere.
I follow many of the guidelines you've been given:
For most trips, I tend to:
- Wear my heaviest footwear choice
- Carry a tote bag
- Layer (in case of cold or heat on plane)
- Wear a scarf/ shawl and/or soft cardigan
- Collapsible water bottle and protein of some kind
- Put reading material on a Kindle
- Stow my laptop in a separate sleeve with chargers. (Love Diana's idea!!)
- Wear an outfit without much metal
- Carry on cosmetics case, esp. for lip balm and moisturizer
- Sleeping mask if a very long or night trip (not that I ever manage to sleep)
- Specs/ sunnies
In suitcase:
Pre-stored cosmetics bag (which I check and edit as required before each trip. This bag includes dental care, hair needs, cleansers, moisturizers, etc. and also bandaids, blister bandaids, emery board, blister stick (for hot weather), Tide stick, etc.
Extra foldable tote (like Carla, I recommend Longchamps or simply stowable nylon bag or backpack, depending on the nature of the trip — and sometimes both; I use these for anything I might purchase and/ or to store my laundry)
Hanging toiletries bag (as Ann explained)
Silicone containers (tube and tubs) (as per Ann)
Tiny first aid kit (keep in suitcase)
Adapters (if going to Europe/ Asia)
When it comes to clothing, always check the weather at your destination (s) !!!
I don’t pack until I have a fair idea of what conditions I’ll be in.
I don’t have a “special” (i.e. separate) travel wardrobe but I do tend to bring essentials in core neutrals (for me, ink/navy, grey, white) with a few statement pieces and scarves. What you'll need will depend on the nature of your work (dress code) and the destinations, as well as what other things you might do at the destination.
For a modern classic style I don’t think you can underestimate the value of a bright jacket and/or coat in a travel capsule, esp. if you respond emotionally to colour (see Angie's posts about her travel for examples). I like stripes as my main pattern on a trip. Clothes that don’t wrinkle much are great, but I don’t actually find wrinkling much of a problem overall and don’t bother with a steamer since most places have an iron or steamer on site.
Gear: I always do something active while I’m away so I try to consider what I will need and pack for it.
Footwear. Conventional wisdom says bring one or two pairs of shoes; Suz wisdom says bring as many as will fit in your bag, and even consider going from carry-on to stowed bag if you can't get enough shoes in (depending on whether you have connections, etc. of course.)
Note, I walk almost everywhere and won’t wear gear as fashion, so my needs may be idiosyncratic, but the only trips where I can get away with two pairs of shoes are two day trips where I won’t have a chance to do anything except work. On a recent two week trip to the west coast of Canada, I thought I was doing really well with four pairs of footwear. Hiking boots and indoor crosstrainers (for gear activities, not fashion). One pair of waterproof booties and one pair sneakers for actual wear. In fact, I could have used another pair of boots for the rain because my trusty Aquatalias soaked through several times. Had I been able to leave them to dry out properly it would have been much better.
But I admit, my travel needs are a bit unusual, so your mileage may (literally) vary!