Keep headers/logos under 125 pixels high. It takes up valuable viewing space, especially for laptop users, that is best left for the good stuff to appear"above the fold." Take a cue from the big companies, simple logos done well say it all. This is our #1 pet peeve - screaming logos and headers!
I back my blogs using a plugin WP DB Backup up. I can restore my blog to the 13, if anything happens. I use my site to be scanned by WP Security Scan plugin that is free and requests that are suspicious-looking to be blocked by WordPress Firewall to fix wordpress malware.
Also, don't make the mistake of believing that your hosting company will have your back so visit this site right here far as WordPress backups go. Not always. It's been my experience that the company may or might not be doing backups, while they say that they do. Take that kind of chance?
A snap to move - image source If, for some reason, you need to relocate your website, like a domain name change go to this site or a new web host, getting your files at your fingertips can save you oodles of time, hassle, and the need for tech help.
Now we're getting into things specific to WordPress. You have to rename it to config.php and modify the document config-sample.php, when you install WordPress. You will need to set up the database facts there.
Implementing all of the above will take less than an hour to finish, while creating your WordPress website more immune to intrusions. Over 1 million WordPress sites were this past year, largely due to preventable security gaps. Have yourself prepared and you are likely to be on the safe side.