File size design suggestions

I have a job to design a 12 pager for digital print (preferrably in colour) but then need to convert/create a PDF that's as small a file size as possible (can be grayscale).

Does anyone have any suggestions/tips as to how I can create a good design for print but then convert to a small PDF - ideally looking at a final 100k file size.

File size design suggestions

100kb is really small! Use only text and vector art (and not a complete high-rez world map -- simple vector art). Do not use bitmaps anywhere. The old adage ''an image says more than a 1000 words'' may be true, but it typically takes up a 1000 times more memory as well. Note that some special effects in InDesign may create bitmaps (shadows in particular).

Grayscale instead of color is really a very minor optimisation. An entirely colored vector image may use 1 byte for a grayscale value, and 3 extra bytes (or 4, for CMYK) for color. It's only with bitmap images that these sizes really kick in.