It's pritty eezy! But yoo'll need to do it under the "Edit HMTL" tab in Blogger (not the "Compose" tab) sinse yoo need to hand-code it.
Dear Skeez -
we was wonderin' how to do "strike throughs" on our text. Da only options we sees available are: bold, italix, color, size.
The tag for a strikethru is <strike> . So yoo put <strike> beefore whut yoo wunt to strike thru and cloze it with </strike>
So to make it look like this:
yer code will look like this:<strike>SKEEZIX</strike>