You would be better have two builds vs two build steps.
The first (Build A) would have 1 build step that would do the building then the second (Build B) would just do the deployment in one build step using the artifacts from the first.
So under the first configuration tab of build A, you would specify the artifacts that would need to be made available from the first build. You can then run the build and confirm that under the artifacts section everything you need is available. (These will show when build A has completed running).
Then under the dependencies section (Can't remember the exact name, and I'm away from my TC instance) of Build B you can set it up to use the artifacts of build A which would then be used for the deployment.
Once you have all that working, you could add a build trigger to have Build B run after a successfull execution of Build A, then if you at one point just wanted to run Build A, disable the trigger on build B or pause the Build B configuration which will stop the trigger from firing.