Keep a careful watch on external dependencies.
External things such as deliveries, contracts, and approvals that could delay your project if late.
They may not be your direct responsibility and are out of your control, but you need to keep watch that they are getting done and that dates are not slipping.
Deliveries are a big one here. You should make your suppliers aware of your project schedule (or the part relevant to them) to emphasise the importance of the delivery date you require of them.
Don’t say you need it by a certain date if that date is the actual date you will install it. You need to allow time for delivery, unpacking, checking, and moving to the site.
