I'm an EU national with permanent residence applying for UK naturalisation. I have ticked all the boxes as far as I can see - and am using the online application rather than the paper one. I must say - this online application is not clear at all - almost diabolical

My question - once i've filled in the online forms - what happens after I pay? I saw some mention here in some closed threads of uploading scans of all my documents? There is no mention of this in the online form. I'm very reticent to post all my original documentation and passports.
Thanks,