If you use Adobe Illustrator follow this step :
1. Write the text you want.
2. Go to at top menu in Adobe Illustrator choose Type > Glyphs to show all character.
3. Select Character that you want to change.
4. In the glyph menu box change the “Entire Font to Alternate For Current Selection”.
5. Explore your Creativity.
This picture may help → http://goo.gl/YrPHgZ
Any question? Feel free to contact me again