Building Fence

I'd like to install a fence on my property using 4x4 posts attached to metal brackets set in concrete. Would like to hear from anyone with experience who could share tips, problems to avoid, etc. One question is how to drill the holes true to run the bolts through one side of the bracket, through the post, and out the other side of the bracket.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
Add image file
Upload is a website for homeowners and building and maintenance pros. It is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.