The short answer is don't give work to "expensive" lawyers. Find ones who deliver value for money.
Is your preferred restaurant, car, perfume, or computer expensive? You're a poor consumer if you don't focus on value for money.
Nan Waldman and Elizabeth Baum have already provided here [on Quora] appropriate clues on what a client can do to minimise costs. Most practices they note relate to client side document management, planning documentation, and communication of strategic intent.
Much more could be written to expand on those topics and extend them to related useful management practices. But the basic principle of cost reduction ON THE CLIENT SIDE is well introduced by their answers.
I want to turn to three suggestions for a client seeking value for money ON THE LAWYER SIDE. My focus too is on non-litigation legal work. Litigation lawyer assessment for cost and time minimisation involves different considerations.
First, seek a relationship with a lawyer you trust. This is a person who exhibits a desire to work with you and over time come to understand your activities, business and market. This lawyer will take your enquiry professionally and explain how the work might be done and costed, in stages if appropriate. This topic is about the importance of culture in the relationship between client and lawyer. The lawyer's personality should be in synch with the client's.
Seek signs that this lawyer exhibits a concern to grow with you, rather than bill for one-off high margin work. This lawyer is best found through personal referral networks or reading and assessing what that lawyer has written. Seek out the lawyer's writing, assess if it displays the thinking suiting your desired approach. How often, how much, and how useful is the lawyer's writing online.
Second, when contacting a lawyer ask if the lawyer can provide "code for re-use". This is critical for achieving integration and standardisation in business or organisational practices. Contractual provisions and formats can be written or designed poorly or well. In many respects drafting contracts (long and short) is very comparable to writing software code. The better written and designed contractual provisions and formats lend themselves to reuse. The more contracts and related documents you get the trusted lawyer to prepare for you, the more code you and your lawyer will have for reuse. That drives down cost and time.
There's a great deal more to say about that last topic but in the interests of brevity I'll turn to another cost and time minimising suggestion.
Third, use of IT is one of the key ways to reduce cost and time. Check what know-how the lawyer has in place for this. Ask simple questions such as:
a) Do you touch type?
b) How experienced are you in the use of a wordprocessor?
c) What is your firm's range of template documents relevant to my area of interest and did you draft them yourself or supervise their customisation?
d) What non-contract tools for speeding up work can you provide for my area or type of work, eg questionnaires, checklists, instruction sheets, procedure tables, and graphics illustrating workflow?
e) How proficient are you in expressing legal tasks, thinking or requirements in spreadsheets and in graphical presentations?
In summary, lawyer side considerations include the lawyer-client cultural fit, the lawyer's document drafting skills, and the lawyer's use of IT and moreover IT software skills, utilisation and talent.