I have been driving with just a manual for a few years now, but I know i need to practice w/clutch to crack into the top 100 of the LB’s.
I have swapped the clutch with the handbrake so thats done, but I am just finding it really hard to switch gears (especially gearing up)
Any tips will be greatly appreciated 
This is what I have found the best for all scenarios and what I use so give it a try, LB upshift, RB downshift, A clutch as you already have it. You could use the double button mash method but I found you tend to get gearbox damage with Sim damage on over the course of the race, not that matters to much. By now I am just use to my method.
You’re fully used to manual yeah???
All you should need to do is use your thumb, hit A first and keep it down and knock gear up or down. It’s a very quick motion you just need to keep doing it over and over.
The first thing you could try is hitting them together at the same time then pop in a minute delay between hitting A first then the X-gear down or B-Gear up.
Ergonomically its the easiest way and closest to normal manual. It’s sounds as though you’re giving up too soon. Keep doing it and it gets easier… I was the same once LAPS LAPS LAPS LAPS Just do as many Laps as you can. You don’t even need to take your finger off the accelerator.
Just remember… It’s only one more button next to the button I have to press anyway!!!
GEARING UP is more of a nudge to the right of your thumb. Don’t over think it just play and it will happen
I think there’s only really 2 methods to do manual clutch using the controller.
I chose the A+LB/RB combo. It was really clunky in the beginning. Took couple of hours to get used to it, a week to become decent at it, now I don’t even think about it.
I have small delicate fingers so A/X-A/B method was not working for me.
Choose a method that feels comfortable then don’t look back.
Exactly, you just gotta practice. I can’t use the LB/RB method as a find throttle control to difficult with any other finger than my index finger so RB doesn’t get a look in on my controller lol.
What do you mean you are having trouble upshifting? What is the issue. A+x or a+b at the same time. Don’t over complicate it. Where it gets hard is the quick downshifts and not stalling. Must rev match better than just manual.
I found it easier when I switched my up/down shift using X/B. I shift up with X and down with B.
I’m finding FM5 with the new Xbox One controller a bit trickier to get use too. In FM3, FM4, and Horizon, i ran with A as clutch, B and handbrake, and LB/RB shifting. I did fine with racing, driving, and even drifting. However now in FM5 i am finding the new bumpers and pressing A an odd combination. I just need to get use to it, but i keep missing gears now.