I have adjusted my text, so it's like an A4-paper. But my header and footer have not aligned. In my preamble I've got:
\usepackage{graphicx}
\usepackage{epstopdf}
\usepackage{float}
\usepackage[normalem]{ulem}
\useunder{\uline}{\ul}{}
\usepackage{epstopdf}
\usepackage{float}
\usepackage[normalem]{ulem}
\useunder{\uline}{\ul}{}
\usepackage[T1]{fontenc}
\usepackage[table,xcdraw]{xcolor}
\usepackage{multicol}
\usepackage{adjustbox}
\usepackage{array}
\usepackage{wrapfig}
\usepackage{multirow}
\usepackage{tabu}
\usepackage{rotating}
\usepackage{amsmath}
%\usepackage[table,xcdraw]{xcolor}
\usepackage{fancyhdr}
\pagestyle{fancy}
\linespread{1.5}
\usepackage{times}
\usepackage[none]{hyphenat}
\sloppy
\usepackage{hyperref}
And in my main script I've got:
\documentclass{article}
\input{z.preamble/preamble.tex}
\usepackage[a4paper, total={6in, 9in}]{geometry}
It looks like this in the pdf:

PS: don't mind the weird letters, it's just an example, so you can see it, thank you.
geometrypackage before the packages which modify your header, i.e. beforefancyhdr– samcarter_is_at_topanswers.xyz Jan 07 '19 at 16:08timespackage, it is obsolete – samcarter_is_at_topanswers.xyz Jan 07 '19 at 16:09