Time blindness is a common problem for people with ADHD, so equally hard is estimating the time it will take to complete a task.

Set an alarm to go off every 10 minutes, or which ever chunk of time works best for you.
Account for breaks.
Use time tracking apps
Time yourself
Use Historical Data
Assess how long it took after you’ve completed the task
Combine the steps to make a schedule
Check you have the time in your schedule
Decide Who You Need to Involve
Gather everyone involved
Get feedback on your estimation
Estimate someone else’s time
Imagine how long you think it would take someone else to complete the task.
Have Someone Else Estimate for You.
Use a three point estimation
- best-case scenario
- worst-case scenario
- most realistic scenario
Understand What’s Required
List all the steps
Bottom-Up/Inside view estimating: break it down into atomic tasks
Top-down/Outside view estimating: look back on previous projects that might be similar shape/size/complexity and see how long they took
Estimate the time required for each step
Order These Activities
Add in extra time
Always overestimate your time requirements 2x-3x
Estimate in Ranges
Multiply & divide your estimate by 4, that gives you the lower-end and upper-end of your range.
Calculate Your Fudge Ratio
Create and refine your fudge ratio (actual time/estimated time)
Make your estimate when you’re feeling tired or unmotivated.
Track your confidence in the estimation and use that to get a better picture of what different levels of confidence indicate

Estimating time for tasks

How can I help myself be less time blind?