Recently I was learning the Anglo-Saxon Futhorc as depicted in the famous rune poem and thought it would be cool to be able to type these myself.
For those interested, this strategy is designed to work on linux. A vastly different approach will be necessary for other systems.
ᛁ ᚳᚪᚾ ᚾᚩᚹ ᛏᚨᛁᛈᛖ ᚦᛖ ᚱᚢᚾᛖᛋ ᚪᛋ ᛁ ᛋᛖᛖ ᚠᛁᛏ, ᚪᚾᛞ ᚹᛁᛚ ᛋᚻᚪᚱᛖ ᚹᛁᚦ ᛣᛖ ᚻᚩᚹ ᛁ ᛞᛁᛞ ᛁᛏ.
(I can now type the runes as I see fit, and will now share with you how I did it).
First is to locate the xkb symbols directory for who have xkbmap installed. For me that would be in “/usr/share/symbols”.
Next, since I prefer to use the workman keyboard layout, I made a copy of that file as workman_futhorc. But in your case, you may want to copy “us” to “futhorc”. And edit that file.
In it, you see a table that lists keys as xkb would recognize them, then beween curly braces an array of what the item should be as lowercase, uppercase, and optionally when an Alt modifier key is pressed. In your modified file, you can type U<code> for a unicode symbol, (e.g. U16CB for Sigel, the ᛋ rune).
Save the file. Test it by running “set xkbmap futhorc,us -option grp:alt_shift_toggle” If you start typing in runes it works! If you want to go back to your normal layout, hit the left Alt+Shift keys.
You can find my file for reference here.