Anchor the debate on your terms
Strike early and set the terms of the debate around your agenda.
Build your coalition
Manage disagreements in private, let people change their view without loss of face and publicise any agreements widely to build a bandwagon of support. Find powerful sponsors to endorse your position.
Build incremental agreement
Do not scare people by asking for everything at one. Ask individuals to back the one part of your idea where they have relevant expertise (finance, health and safety etc)
Size the prize
Build a clear, logical case that shows the benefits of your proposed course of action, and then quantify the benefits and have them endorsed appropriately.
Frame the decision favourably
Align your agenda with the corporate agenda, frame your idea in the right language and style for each person, and be relentlessly positive.
Do not give too many options as it will tend to confuse. Offer two or three choices at most.
Work risk and loss aversion to your favour
Show that alternatives to your idea are even riskier.
Put idleness to work
Make it easy for people to agree by removing any logistical or administrative hurdles for them.
Repetition works. The harder you practice, the luckier you get. Never give up.
Adjust to each individual
See the world through their eyes, respect their needs in terms of substance, style and format, build common cause, align your agendas.
Owen, J., 2006. How to manage. Pearson Education.