How do I save data after the cursor back to the first field on the page Add new record.

any idea?

Can you give more detail?

In the first part of the question (how do I return the cursor in a particular field after the data is saved) was solved using Internet Explorer was using mozila and always had to make a click in the field to start to fill in the data.
In the second part (And how do I click a field to clear its contents?). I use a barcode reader to fill out data in a field sometimes he reads the wrong code, i have to delete the fields. What I want is when I click on the field (to focus) it wipe its content. I know I have to use JS but do not know how.
I do not speak English and I use google translator to write my questions, so my questions are sometimes a bit strange.
Thanks for the help and sorry for my english.