You probably noticed that there are two types of C chords in the chord chart. You can play the second type where the word Partridge falls in the lyrics. This is not necessary though, you can play the basic chord as well.
Here are the lyrics to 12 Days of Christmas together with the guitar chords. The chord changes are rather quick, so you better start practicing this song well before Christmas day.
First day:
C G7 C
On the first day of Christmas my true love sent to me...
C F C G7 C
a partridge in a pear tree.
Second day:
C G7 C
On the second day of Christmas my true love gave to me...
G7 C F C G7 C
two turtle doves and a Partridge in a pear tree.
Third day:
C G7 C
On the third day of Christmas my true love gave to me...
G7 G7
three French hens, two turtle doves,...
C F C G7 C
and a Partridge in a pear tree.
Fourth day:
C G7 C
On the fourth day of Christmas my true love gave to me
G7 G7 G7
four calling birds, three French hens, two turtle doves,
C F C G7 C
and a Partridge in a pear tree.
Fifth day:
C G7 C
On the fifth day of Christmas my true love gave to me
C G7 G7
Five golden rings,
G7 G7 G7
four calling birds, three French hens, two turtle doves,
C F C G7 C
and a Partridge in a pear tree.
Sixth day:
C G7 C
On the Sixth day of Christmas my true love gave to me
G7
Six geese a laying,
C G7 G7
five golden rings,
G7 G7 G7
four calling birds, three French hens, two turtle doves,
C F C G7 C
and a Partridge in a pear tree.
Seventh day:
C G7 C
On the Seventh day of Christmas my true love gave to me
G7
Seven swans a swimming,
G7
Six geese a laying,
C G7 G7
five golden rings,
G7 G7 G7
four calling birds, three French hens, two turtle doves,
C F C G7 C
and a Partridge in a pear tree.
Eighth day:
C G7 C
On the Eighth day of Christmas my true love gave to me
G7
Eight maids a milking,
G7
Seven swans a swimming,
G7
Six geese a laying,
C G7 G7
five golden rings,
G7 G7 G7
four calling birds, three French hens, two turtle doves,
C F C G7 C
and a Partridge in a pear tree.
Ninth day:
C G7 C
On the Ninth day of Christmas my true love gave to me
G7
Nine ladies dancing,
G7
Eight maids a milking,
G7
Seven swans a swimming,
G7
Six geese a laying,
C G7 G7
five golden rings,
G7 G7 G7
four calling birds, three French hens, two turtle doves,
C F C G7 C
and a Partridge in a pear tree.
Tenth day:
C G7 C
On the Tenth day of Christmas my true love gave to me
G7
Ten lords a leaping,
G7
Nine ladies dancing,
G7
Eight maids a milking,
G7
Seven swans a swimming,
G7
Six geese a laying,
C G7 G7
five golden rings,
G7 G7 G7
four calling birds, three French hens, two turtle doves,
C F C G7 C
and a Partridge in a pear tree.
Eleventh day:
C G7 C
On the Eleventh day of Christmas my true love gave to me
G7
Eleven pipers piping,
G7
Ten lords a leaping,
G7
Nine ladies dancing,
G7
Eight maids a milking,
G7
Seven swans a swimming,
G7
Six geese a laying,
C G7 G7
five golden rings,
G7 G7 G7
four calling birds, three French hens, two turtle doves,
C F C G7 C
and a Partridge in a pear tree.
Twelfth day:
C G7 C
On the Twelfth day of Christmas my true love gave to me
G7
Twelve drummers drumming,
G7
Eleven pipers piping,
G7
Ten lords a leaping,
G7
Nine ladies dancing,
G7
Eight maids a milking,
G7
Seven swans a swimming,
G7
Six geese a laying,
C G7 G7
five golden rings,
G7 G7 G7
four calling birds, three French hens, two turtle doves,
C F C G7 C
and a Partridge in a pear tree.
Also check out Jeff Foxworthy's Redneck 12 Days of Christmas version: