Whenever possible I prefer to take out the toilet. If not, I tend to mark a couple of datum lines on the subfloor and measure from there. Paper felt round the toilet/pedestal and transfer onto the plywood. Keeps the joins to a minimum too
In matt's example's I would suggest are at worst lazy fitters just using the first straight edge they can find (poss the manufacturers) or at best the shop didn't allow enough material to balance the pattern. If there was enough material they could have balanced the pattern without a template. For a small bathroom or ensuite I have in the past put the sheet of ply on top of a double bed to mark out if the weather is bad or extremely windy and they have no garage or other space. And yes on occasion split a sheet to get it into the room, trying of course to keep any splits away from main traffic areas and feathering in the joints. I have used neighbors garages or carports or if close enough gone back to the store to template it out. You do what you got a do..
Ive had my sheets split into 3 sometimes, makes it a lot easier and you can usually template in the hallway/landing (even stay in bathroom sometimes) if weather is that bad but Ive never templated cushion floor, concave/hook it straight in. Safety vinyl then yes but not cushion floor. If im with one of my subby mates then we use the back of his iveco, its built like a tower block plenty of room.
When making a template to mark round toilets and architraves I use a square on the straight edges but is there a good way to get accurate curve marks?
Use your straight edge and pencil long lines each inch you move it around the toilet, not just small pencil mark like dot to dot if you get what I mean, eventually the pencil lines you have marked join up where they criss cross giving you the radius of the toilet/pedestal for you to then be able to cut perfectly. Works for me all the time. 4mm ply I use a concave to score and cut and with the decent 6mm but usually use my cordless jigsaw. Architraves I undercut with my multitool, makes life a lot easier and looks a lot neater that cutting in and out of the fancy shapes these architraves have these days.
That's the old skool long way round the houses method There is a much quicker easier way to template round the pot
I do it the old school method too! How the hell can you do it quicker spacey? Unless you cut it in around the toilet etc?