Hope you were able to build the simple PIC 18F programmer and 18F4550 development board with help of my previous posts.Now it's time to program the 18F4550 with bootloader in order to use for our future projects.Using bootloader eliminate the need for a dedicated programmer and also it's really easy to edit our programs and reprogram the PIC while developing.
I'm using the boot loader available at OLIMEX.you can find the link at the bottom of the page.
You can use WinPIC 800 as described on simple PIC 18F programmer page.If you use any other programmer,please program appropriately using following configuration bits.
When it's succeeded just plug the PIC to development board.Now you can use it's USB port to program PIC and do wonderful projects using the development board.
You can use this little app to program PIC using bootloader and that article give you great information on using that too.
Evans page on USB bootloader
EDIT:Link seems to be dead now.check this backup:
Backup as PDF
Good luck!!! :D