1. PACK AS LIGHTLY AS POSSIBLE
When packing, it pays to be selective. So, when you're loading up your case, ask yourself whether you really, truly plan on wearing something. If the answer is yes, then consider whether said item is performing a completely different sartorial function to anything else in your case. It's the easiest way to strike a happy medium between maximum outfit options and minimal excess baggage.
2. DON'T CARRY EMPTY SPACE
Think you've filled your suitcase? Think again. Make use of space containing objects (such as shoes) by filling with socks, and in the process maintain the shape of your shoes. It's win a win situation.
3. PLAN WHAT YOU'RE GOING TO WEAR AHEAD
It may sound overly organised, but planning what you're going to wear (roughly) day by day according to your holiday agenda is the smartest way to get the most out of what you're wearing. Jot down each outfit you're likely to wear using staples (such as trousers or jeans) for multiple outfits. It will save space and avert headaches over what to wear when you're getting dressed in the morning, leaving more time for you to explore your new surroundings.
4. GO LIGHT ON YOUR GROOMING ESSENTIALS
It goes without saying that you should only pack the very smallest amount of each of your grooming essentials (so not a full size tooth paste tube) but make sure that you find the smallest wash bag possible to save on space when travelling too. Not as obvious, but frees up valuable suitcase space.
5. SUITS GO ON THE BOTTOM
There's no ideal way of putting your beloved suit into transit. Fact. However, there are wise and not so wise ways to take your tailoring on a trip. Make sure that your tailoring is packed in a suit bag at the very bottom of your suitcase. This way it won't move around and will be less prone to irksome creases.