Please bear with me, I'm not a graphic designer so my terminology may be wrong. I'm busy designing some milestone cards which are 6x4in in size. I'm making over 20 so in order to keep printing costs low I can fit three of these 6x4in cards onto one A4 size page. What would be the best way to add these to an A4 page and save in pdf, without compromising the quality. I tried to import the each png file into a new A4 size Inkscape document but the graphics became pixelated. I then tried to import the three svg files into an A4 inkscape document but it didn't keep the 6x4in page size, so when I print it I have no idea how to cut it out because there is no border to guide me. I really hope this question makes sense and I'm sure it's not complicated but I have no idea how to figure this out. Thanks.

I tried to import the each png file into a new A4 size Inkscape document but the graphics became pixelated.

That must mean that the images are imported at something besides their original size. Check Inkscape Preferences > Bitmaps, and make sure the Import Resolution is set for 96. If it's anything except for 96, it will not keep the same size (as far as I understand).

I then tried to import the three svg files into an A4 inkscape document but it didn't keep the 6x4in page size, so when I print it I have no idea how to cut it out because there is no border to guide me.

This could also be related to the wrong import resolution, if the SVG files contain some raster contents. If that's not the case, we might need to look at one of those SVG files, to find the problem.

If you want a border showing where to cut, you could just draw a rectangle. But if the SVG contents are the wrong size, then the rectangle will probably be the wrong size too.

Someone else might already know exactly what's wrong. And I'm sure they will reply, if so. But for myself, I would probably need to see one of the 6 x 4 SVG files, for testing.

Which is your preference - import the PNG version, or the SVG version?

How do you 'import'? Drag and drop? Are you using a Mac?