If you want to engrave a motto or something similar, put it in latin. It doesn't matter what you say, really, but putting it in latin makes me it feel 'smarter' and 'enlightened' to most people. Most people also don't know what it means, but if you know what it means you can tell him or her and it could either by their secret little motto between you guys or he/she could be proud and feel smart, showing it off.