I have a sequential list workflow and the tasks created for that workflow is stored in a custom task list. Now whenever the task in custom task list is edited it should go to my custom aspx page in layouts folder so that i can edit the task. How to do it. Please send me some useful links for achieving the same.
You can use custom content type for your workflow task form. In this content type you have to set links to your ASPX page. However, there is an issue inside SP that you can't set custom forms using XML declaration if your content type is inherited from another. You can do that from code. I wrote an article about that on my blog. You can find it here: SharePoint 2013 Workflows. Part 2/3: custom ASP.Net task form
It should help.
You can create your custom edit form by opening your workflow in Sharepoint designer and under 'Forms' option you can create your own edit form and set it as default edit form.