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 up my blogs regularly using a free plugin WP DB Backup. If anything happens I can always restore my website to the settings. I use WP Security Scan plugin to scan my blog and WordPress Firewall to block requests that are suspicious-looking to clean hacked wordpress site.
Everything you have worked for will go with this, should the server of your site go down. You'll make no sales, get signups or no traffic to your site, until you have the site back up 32, and in short, you're out of business.
Recently, an unknown hacker hacked the site of Reuters and posted a news article that was fake. Because of what the hacker did since Reuters is a news site, their reputation is already destroyed. If you don't pay attention on the safety of your WordPress 20, the same thing may happen to you.
You could even get an SSL Encyption Security to your WordPress blogs. The SSL Security makes encrypted and secure communications with your site. You can keep the all of the cookies and history of communication so that all transactions are recorded. Make sure all your sites get SSL security for protection from hackers.
Change your WordPress admin and password username, or at least your a knockout post password and collect and use other fantastic WordPress safety tips to keep hackers out!