Top tips:
1. Use the stakes with bolt tighteners, not the god awful interference fit ones!
2. Drill a pilot hole as stated earlier, not a massive one, but you want to know there’s nothing problematic you’re going to drive the stake into, i.e. builders rubble, stone, concrete, etc.
3. Have a foot long 75×75 off-cut to put in the stake, this will be how you drive it in.
4. They’ll twist, offset to correct this, getting them straight is easier as you can be off slightly but correct with the post in and with the fence panels or rails, so just check that it’s within limits with a spirit level every so often.
5. Have a way of getting them out if required, i find a decent spade and some type of lever under it works well, you get the spade edge under the spike and can then bring it back out with a bit of bodyweight.
It’s not that difficult if you prep a bit, if you’re using spikes then it should be for softish ground anyway, with no rubbish underneath, they go in easy for that, just watch out for twisting, if they do, just whip them out as per 5.
6.