How to decrease photoshop picture file size

[thecremeegg]

Having issues with my new sig - cant get it below 40kb when saved as a JPG. What would be the best way to go about shrinking it? Cheers

 

[thecremeegg]

save it as gif go to file/save for web then change all the settings to get it below 20kb

Cheers for that, worked a treat