After you have set up your page size by adding the .25"with the borders set to B+ (outside the image), you can do it by selecting the 'crop marks' option in the Edges popup dialogue box below the preview screen.It will show the corner marks for trimming purposes.
I do this for printing multiple gift card layouts. The only thing that bothers me a little is when I have the cards layed out with the space saving feature and the cards are right next to each other, you inevitably show the mark slightly on one side or the other after the trim. You would have to trim just inside the marks if you don't want to see them,  since even though they are thin, they are black and show if your not exactly inside the marks on the trim. I wish there was a way to make the marks just barely visible, a very light gray for instance. ;-)

From Help Menu....
Mark Edges - Click the "Job Properties" tab on the bottom/right of the main window and check "Edges" to produce crop marks or a thin outline around each print to aid cutting.

The two options below produce lines that extend past the edge of prints to aid cutting.  Be aware that since crop marks and guide lines extend beyond the edges of prints and into "unused" portions of the paper, they should not be used if you intend to reuse/refeed the paper into the printer at a later time in order to use more of the paper.

Crop marks*: crop lines that extend 1/4 inch from all four corners of each print.
Guide lines*: guide lines for cutting extend from all four corners of each print all the way to the edge of the printable area on the paper.
* Note: crop marks and guide lines will not print on corners/edges that are too close to the printable margins of the paper.  Unless borderless printing is selected, your printer will not be able to extend the crop marks/guide lines all the way to the edge of the paper due to physical printer limitations.


 

Hi
Just to clarify Ray's method, you set the 'Border 1' colour to grey and width to zero then 'Border 2' to your .25" margin and White, then choose 'Mark Edges, use border color'.


Brian

Brad,
Excuse me for butting in, but I need to understand. The print sizes vary inside the template, plus a .25 inch white border, and you want guides for trimming
Please see attached screen snap, and point out what is missing that you require.
I have trim guides at the edge of the print and again at the edge of the template.

Fred

PS  Terry et al will try to help. I have to leave for a :Stress Test" in a few minutes.
As if the forum wasn't a stress test enough!     

Just a quick question....  Which printer are you using... so I can get 2 x 12 on a 24" roll?

Fred

Don't have the driver for that one, but I tried on an Epson 7800

I just put different size images in the templates for effect.
I think that the  trimlines are there but get lost because you have the four 12" templates jammed together.
If you look at #009 from a few posts ago, which was a single template, you can see all the trim lines, images and templates.
That's why I suspect the timlines are there but covered.
I cannot make the print because I don't have a printer that takes 24" rolls.
Make a test

Fred

I think this is resolved! My assumption about "Edges" was wrong in the case of templates. With a template, the trim lines are placed around the template, not around the image inside the template. If there are templates 2-up or 4-up, all the trim lines are visible. It works like a charm, all I had to do was try it! Thanks Fred.

BTW, I discovered a way to simulate these jobs regardless of what printer you have--just print to "Adobe PDF" and set the paper size at 24" x 16" or whatever. Not only does it work, you get a PDF that shows all the trim lines. Sweet!

Cheers and thanks again.

Brad