The three-time world champion, who edged out the Rocket 6-5 on Friday, is bidding to become the first player to win two Home Nations events in one season having also claimed the English Open with a sensational 9-1 triumph over Gilbert, missing just seven balls in the process.
This was another one-sided affair, with the Leicester cueman compiling breaks of 132, 84, 76 and 69 while his opponent's only frame came when he was 4-0 down.
Selby will now face Jack Lisowski, who beat Mark Allen, over a best of 17 final on Sunday, with the winning picking up a cheque of £70,000 and the Stephen Hendry Trophy.
He told worldsnooker.com: "Gilbert is a great lad and a great player. We have practised together a lot over the last few seasons. I know what he is capable of. I was always on my guard out there. I tried to keep it tight and not give him too many chances as he could easily have done what I did to him to me.
"It would be fantastic to win here. I have the Steve Davis Trophy at home and if I win tomorrow I will add the Stephen Hendry Trophy. I have a tough test whether I am against Mark or against Jack. I just have to rest up and go again."
Gilbert, whose wait for a ranking title continues after missing out on a fifth final, said: "I didn’t expect anything from this week. However, after beating Judd Trump 5-2 last night I thought I would turn up and play like that again. I’m not saying I expected to win, but I felt I’d play well.
"I’m looking forward to playing in the Masters in January. I haven’t been there before, everyone tells me how mental it is. There are a lot of people there watching so it will be different from anything I have experienced. Hopefully I do myself justice."
Lisowski overcame Allen 6-5 in a thrilling contest to reach his third ranking tournament final.
The opening session of the second semi-final was shared 2-2 with Lisowski firing breaks of 135 and 82, and Allen producing a clearance of 77.
Allen followed that up with a 79 clearance to lead for the first time before Lisowski fired breaks of 59, 118 and 74 for a 5-3 advantage.
The Northern Irishman edged two tight frames to set up a decider, but Liskowski's potting brilliance came to the fore again with a match-winning 95.
