Surely the same as any other tyre.
My two pref ways are:
lots of Fairy, then marginal over-inflation and leave for a while, then maybe the following in addition.
Pump up to a reasonable (mid range) working pressure and properly grabbing out the bead where it needs to be.
Bead needs to come out at one point .. make it 12 o clock but facing away from you.
Palms over the tyre then pinch in and pull up the bead with your fingertips two handed, like your massaging the bead out with your fingers
one foot over the tyre at 6 o clock may help with leverage.
Could just be guff molding .. have you checked 'that line' marking the bead is giving a consistant margin around the rim?