I use manifestation for business all the time - seems pretty practical to me.

If you have a schedule or you need capital or resources, just add those requirements into your box request.

If you're going to start getting into the area of desperate need regarding a request (bills are piling up like clockwork) or you cannot take your attention off a request, or you are in a rush then you are probably going to have to work on neutralizing the negative emotion you have regarding the subject before it manifests...though it can sometimes still come anyway if your desire is strong enough.

If you are in this situation and you can move your vibrational setpoint on the emotional scale to, at least, Hope then you will start seeing physical evidence of your manifestation coming. This more deliberate approach is mostly what I use my manifesting spreadsheet for. (An interesting observation from this is that the only time delay in something manifesting is the amount of time it takes you to move up the emotional scale)

Also, if your requests are large and complex but they can be split into smaller targets, then break down the larger requests into several smaller ones.