Right now this is a bit of a problem for me too. I just guestimate based on previous work and hope nothing goes wrong or nothing unexpected crops up. In the eve

Right now this is a bit of a problem for me too. I just guestimate based on previous work and hope nothing goes wrong or nothing unexpected crops up. In the event where it's something I've never worked on before, I do a bit of research and try gauge the difficulty by seeing how hard the subject is, how many resources are available (tutorials, articles etc) and my estimate here is compared with how long it took me to learn something similar. I have noticed that my estimates are becoming more accurate over time but I'd also like to know if people have some sort of a procedure/workflow that they follow. Another approach I experimented with was using the scrum methodology. I tried breaking the tasks up into smaller chunks (user stories) and then valuing the effort/time required for the individual parts before adding the values up.