i would not highlight in the photocopied page itsself, since the stamp itsself should look as genuine as possible (especially because in some countries they could b easily faked)...i had a lot of headache to work preparing my document with stamps and and re-did it several times...also i was shocked to see that Canadian passports don't have the passport number on each page (so they could claim i put these stamps for someone else's passport

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this is what i did so far:
1. i made a chronological outline where it explains clearly in a table the date of exit, date of entry, place of entry/exit, event (need of new tourist visa, etc), and which scanned image they should look at
2. the scanning i made it high resolution, colored (for this country, green stamp means entrance, red stamp means exit); i tried in general to scan the whole passport page (so they can see the page number) but in some cases i needed just a stamp from that page, so i scanned only that stamp...
3. if ur entry visa is on page 6 and ur corresponding exit is at page 17, i show them together (page 6 next to page 17) and i explain clearly what they need to follow on each page (entry stamp for this date with exit stamp for that date; if the passport page is not shown, I would write to which passport page they should refer); u don't want them to jump pages, go back, they will b lost
4. i also scanned all my passport, put 4 pages per document and i'll give it as an annexe (attach it at the end of everything, in case they need more and it was not clear)
5. i also found some ticket reservations and boarding passes which could also enforce some of the stamps
6. i'll reference these stamps in my letter (sponsor), explain how i stayed here and the periods; i'll reference them also in the relationship timeline
7. i also gave this document to people to read it and see if they understand something (the 2nd one was clearer than the 1st;))
some countries could give u immigration record (all the entry/exit dates based on ur passport) but many don't; it's worth to ask
what i told u before it's just visas/stamps which emphasize my stay or residency in his country; for the trips together i made it separate and i show his passport stamp next to my passport stamp, his boarding pass next to mine, and common ticket reservation (why need of all, when one is enough u would ask: well, because in case they r not certain of one, they could reference to the second one, and be convinced that we did have trips together);
if u have a lot of trips, i would also do a chronological outline at the beginning as before and on each page explain what those images are (entry/exit stamps to Burkina Faso, 2007; left image: sponsor passport, right image: applicant)
good luck!
