I use a pop-up that comes up at the end of my blog posts, I've used them in various places but find the most sign ups when I put it at the end.
I know I click off a page if the sign up form hits me two seconds after I land so think about that when you decide where to put your sign up.
There's an article here the lists out all the locations on your webpage where you can add an email capture, I have NO affiliation with this site or sites listed here, this is purely a helpful link drop https://blog.kissmetrics.com/capture-email-leads/
I started out with MailChimp because it was free and easy to use, using AWeber now but have to say, cut your teeth on something like MailChimp because AWeber isn't the easiest thing to use.
If you search on "email marketing software" you will find lots of companies that offer free, free trial and paid subscription services.