A few things I have picked up over the years… (everyone got their egg inhalation gear ready?)
1. Get a good grip on your ratio. DAFNE types get introduced to this early on, but it took me years of winging it before properly thinking of adjustments in terms of 10g carbs = x units of bolus
2. Testing after meals. Testing before was always a given, but testing after will tell you a lot. Around 1-1.5 and 2-3 hours after are pretty useful. Helps you to identify which foods/meals are spiking your bgs
3. Watch high fat meals (slower carb absorption). And if low carbing don’t forget that your body will probably train itself to create bgs from proteins
4. For massive carb-fest blowouts get to know your insulin’s activity curve. If you suddenly whack in double your normal mealtime dose cos you’re on holiday and are having chips on the beach you may well find that you’ll go hypo after your meal (too much insulin all at once) and then drift high later (as your gut gradually chugs through the stodge). Consider splitting the dose into two or three staged deliveries an hour or so apart.