This web page is about installing a TeX-ready font in a personal directory. A separate page describes the somewhat simpler process of installing new fonts in a system directory. This page will assume you have read the other one, and thus are generally aware of TeX font installation procedures.
This page is only about TeX Live. (If you can tell us the specifics of doing this under MiKTeX, we'd be happy to include that also.)
Here is a general outline for installing fonts in a personal directory:
tlmgr generate \
--dest $TEXMFVAR/web2c/updmap.cfg \
--localcfg $TEXMFCONFIG/web2c/updmap-local.cfg \
updmap
The principal downside of this is that if a new font is installed in the system directories (e.g., via tlmgr update, its map entries will not be installed in these personal .map files. You yourself have to rerun the tlmgr and updmap commands as above.
Another caveat is that if there is a system-wide updmap-local.cfg, for fonts installed locally but not personally, they will be lost. You must insert those entries into your file.
The underlying problem that we have to work around is that the application programs which use TeX font map files (pdftex, dvips, etc.), are only prepared to read one such file (pdftex.map, psfonts.map, etc.) which thus must include every single font that might be used, both system and personal.
Perhaps one day the programs will be changed to look for a map file in each texmf tree. Until then, we just have to make do.
Good luck. If you have technical questions or problems with installing fonts, please try writing texhax@tug.org. For corrections to this web page, contact the TUG webmaster (link below).