I know - they'e SO sexy aren't they!
I'm an OT but also I've had CTS in both pregnancies and befire that following - ironically - in injury while making resting splints.
Assuming you've got pg-related CTS there's not much point in making long-term changes as hopefully you will find itgets much better after you've had the baby - though you may find it gets slightly worse just afterwards as your body retains more water for a few weeks.
In terms of when to wear the splints, don't wear them all the time as you'll weaken your joints but you can wera them a bit more often. CTS as I'm sure you've already been told happens because you out on water in pg which can put pressure on the nerve that feeds part of your hand - the pain will get worse if you inadvertently stress the joints and they get inflamed. To try and prevent this you can wear the splints while doing any activity that strains the joint - gardening, driving, lifting (though you should be cutting down on these things anyway at your stage of pg). But things you do you may not think of as hard can also be included - lifting a kettle/pan, hoovering, making a bed. Just remember to take them off when you've finished.
In terms of kit one hing I would recommend is 2 of those floppy plastic jar openers - (I got a sunflower shaped one from morrisons recently for 99p) one for home, one for your handbag. Use them for jars (obviously) but also whenever you need to switch something on/off that's stiff like a tap, or they're good for round door knobs. It might sound trivial but you do these things so often that if you make that one minor change it can make a real difference.
If the CTS is long term/doesn't go away the go to your GP and get referred to see an OT if you haven't already - there are loads of gadgets and little strategies they'll be able to help you withthat will ease the pain and just help you get on with life.
Also -it might be worth you getting/borrowing a baby sling for those first few weeks - an easy access one NOT the papoose style - just to save your hands/wrists. Newborns are light but you pick them up and carry them around a lot so its worthwile thinking about it.