My preferred technique is to pull out duplicate (or nearly-duplicate) code into functions. Take this:

    Tr(
        td("File: "),
        td(
            filefield(
                -name      => 'upload',
                -size      => 50,
                -maxlength => 80
            ),
        ),
    ),
        Tr(
        td("File: "),
        td(
            filefield(
                -name      => 'upload2',
                -size      => 50,
                -maxlength => 80
            ),
        ),
    ),
[download]

It continues for two more fields, but I'm too lazy to paste that much code. The only difference is the name field, so it's easy to turn into a function:

sub upload_field
{
    my $name = shift;
    
    return
    Tr(
        td("File: "),
        td(
            filefield(
                -name      => $name,
                -size      => 50,
                -maxlength => 80
            ),
        ),
    );
}
[download]

That turns your table into something like this:

print start_form(
    -method  => 'post',
    -enctype => 'multipart/form-data',
    -action=> ''
  ),
  table( 
    ( map { upload_field( "upload$_" ) } ( '', 1 .. 3 ) ),
    Tr( td(), td( submit( 'button', 'submit' ), ) )
  ),
  end_form(), hr;
[download]

The same goes for processing upload fields. Remember to ask the question what's similar and what's different?