Transitioning 2 kids into own bed/bedroom

So I bedshared with my 2 boys since they were born. The oldest is 3 and the youngest is 17 months old. And because of that I haven't been able to sleep in the bed with my SO fully in almost 3 years (not counting the handful of times I did which was maybe like 5 times)

They're used to sleeping with me and now I'm pregnant with baby #3 and I really want to get them in their own beds and bedroom before baby girl is here since she will be sharing a room with me and the dad.

Anyone have any tips on doing 2 at once? I know I waited a long time and made it harder on myself and that it's no one's fault but mine, but I really need them in their own rooms.

I've already made their own space, and am throwing out any old bed frame and mattress tomorrow so I won't be tempted to give up.

Any advice?