To come up with a good estimate, follow these guidelines. Assess the project. Then, decide how many hours the project will take. No project ever goes off without a hitch. Add some hours to account for unforeseen problems.
Some people even advise IPs to double their first estimate.
Multiply the total number of hours by your per-hour rate. Add these expenses up. Then, sell yourself on the price. Present your proposal to your client. Don't offer a breakdown of time and materials.