How to Install a Polytonic keyboard.

Step One

Go to start, select settings, Choose Time & Language,

Step Two

choose Language from left column,

Step Three

click on Add a language,

Step Four

in search window, type Greek.

Step Five

Once it is added, click on the entry, choose Options, under Keyboards, choose Greek Polytonic.

Step Six

Once you have installed it, you can now go to any document to type in English or Greek. To toggle from an English keyboard to a Greek keyboard, hit Alt-Shift. In the lower right corner of the taskbar, you will see an abbreviation of the language you have chosen: ENG for English and ΕΛ for Greek. The placement of the Greek letters are similar to the English keyboard. Thus the a-key gives you alpha; b-key gives you beta. There are some exceptions:
w → ς
y → υ
u → θ
j → ξ
x → χ
c → ψ
v → ω

You need to type the accent before typing the vowel. For example:
;o → ό
]o → ὸ
'o → ὀ
"o → ὁ
[a → ᾶ
{v → ῳ
:y → ϋ

If you try to put a circumflex over an omicron, for example, it is not allowed.
In some of the following examples, you will need to hold down the right-hand Alt key and then type a character. To make this simple for the chart, I use a capital 'R' to indicate the right-hand Alt key. The left Alt key 'L' will not produce the accent you want, only the right Alt key. For instance R;i will produce ΐ but if you type L;i it gives you ί (because it just ignores the left Alt key).

ό ← ;o	ὸ ← ]o
ὀ ← 'o	ὁ ← "o
ᾶ ← [a	ῳ ← {v
ὄ ← /o	ὅ ← ?o
ὂ ← \o	ὃ ← |o
ἆ ← =a	ἇ ← +a
ΐ ← R;i	ῒ ← ~i
ᾀ ← R'a	ᾁ ← R"a
ᾴ ← Rqa	ᾲ ← R]a
ᾷ ← R[a
ᾄ ← R/a	ᾂ ← R\a
ᾅ ← R?a	ᾃ ← R|a
ᾆ ← R=a	ᾇ ← R+a
ϋ ← :y	ῧ ← R`y
’ ← R'

For half-stop · hold down all three together: Right Alt Key, shift key, and ] (right bracket).
For question mark ; hold q and ; (it will produce ;' so you will need to erase the ').