1) You just extend the template, preferably in regular manner.
2) If You want to draw multiple variants You just do it.
There's no rule about it, though personally I prefer to have it spaced horizontally as close to each next 10 meter mark on the scale, and vertically at regular intervals.
These are templates I use. THESE ARE NOT TO BE MEANT AS OFFICIAL TEMPLATES
(though of course feel free to use them)
Long orange lines are for the alignment of vehicles, shorter lines for alignment of captions (descriptions).
Lines around the country/type/author are for alignment in case second line of type description was needed.
First set is mainly for smaller aircraft.
That's a basic template (1000x330), that can fit up to 4 small aircraft (Spitfire for example) or other vehicles.
Size 1000x630, up to 8 small aircraft (or 4 larger in single column). Note that "www.shipbucket.com
" watermark is applied twice, in case the size was to be reduced to 1000x480 (up to 6 small aircraft).
Size 1000x930, up to 12 small aircraft (or 6 larger in single column).
Size 1000x1230, up to 16 small aircraft (or 8 larger in single column).
Size 1000x1530, up to 20 small aircraft (or 10 larger in single column).
Second set is for medium-sized aircraft, like DC-3, Il-14 or An-26, that still fit on 1000 pixels of width, but for 330 pixel height only one would fit, while using previous type templates would leave LOTS of empty space between them (vertically).
Size 1000x400, for 2 medium aircraft.
Size 1000x600, for 3 medium aircraft.
Size 1000x800, for 4 medium aircraft.
Size 1000x1200, for 6 medium aircraft.
Size 1000x1600, for 8 medium aircraft.
Third set is for huge jetliners - like B767, Il-86 or B747.
Size 1250x330, for 1 large aircraft.
Size 1250x630, for 2 large aircraft (each occupying "2 lines").
Size 1350x480, for 1 very large aircraft.
Size 1350x930, for 2 very large aircraft (each occupying "3 lines").
Of course some of the largest aircraft could demand even more extension. Doing such keep in mind to move appropriately the watermark in the lower-right corner.