I used to use just regular oil. Green Kendall IIRC.
If you are not using a special cutter for stainless braided hose, wrap it TIGHT with masking tape where you are cutting the hose, and use a very fine tooth hacksaw to cut. gently take off the tape and immediately put the nut on the end of the hose so the braid doesn't have time to unravel. It can be a pain to get the braid into the nut once it starts to do that.
There is a gap between the nut and the fitting when the fitting is assembled. I think it was slightly different depending on the size of the hose. Earl's used to sell a feeler gauge for this, but it wasn't +/- .005" territory.
Make sure that when you put in the part that goes into the hose, that you don't gouge the inside of the hose and create a flap that can block the hose.
After assembly, we used to run some paint thinner (mineral spirits) through with the ends plugged with thumbs, swish it around, dump that and follow it with brake cleaner.
That's about all I remember. I'm sure that if I missed anything or said something wrong, I'll be corrected.