How to make wmv files clearer?

[Shirley]

Can anyone teach me? Is there a way? Do I need to download any softwares?

[D_Knife]

There's nothing really more than
A - get the best quality source you can
B - use a high (decent) bitrate

Practice on a decent looking short clip and try several different settings - make a not of your current settings in case you want to go back to default
and keep going until you find something that looks good to you

There's nothing to "teach"

[puertorican138]

You could try adding sharpening filters but that won't help that much. :P