What you put in your luggage should match its strength, particularly with soft bags. Overpacking stresses the fabric, catches, zips & handles. Pack soft cases to capacity, as underpacking leaves the material slack & it becomes prone to tearing. Pack hard cases to capacity to prevent unnecessary movement of contents.
Always lock your luggage & securely attach a card with your name & destination (never put your home address as it could alert would-be burglars that you will be away). Simply write your name, airport & country of destination (&/or departure airport & country). Alternatively, write your business address if necessary.
Keep any bottles containing liquid (e.g. shampoo, hair coloring, etc.) in your hand luggage. There is enough liquid, even in a small bottle, to completely ruin the entire contents of your suitcase. Never pack safety matches - they're not completely safe.
A strong webbing strap around the case is a good idea. It will:
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stop case opening in transit
deter pilfering
help with identification
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#label suitcase
Remove old destination labels or airline stickers. A well-travelled case covered with labels may impress your friends, but can confuse airport staff. If you don't want your luggage in Rome, when you're in London, remove all irrelevant labels (or draw a large cross over them with a permanent black marker pen). Take off removable handles or carrying straps & put them in your hand luggage.