Reflect changes made in Yocto recipe

I'm new to yocto world and recently I started working on a yocto project. I have a basic question about how to reflect changes onto a device. I have made changes using devtool modify <pkgname>. Now I wanted to flash it on my device. The way I'm doing this is first building this recipe ( devtool build <pkg-name> ) and then building complete image ( devtool build-image multimodal-image-minimal ). But this process is very time consuming even for very small changes. So are there any other different ways something like updating some iso which can make life easier ?