Hi - you have a few issues:
- You have some broken file references; entypo.min.css and zshare.png, the former is hanging and causing a long delay trying to fetch it
- Your images are too big in terms of Kb. Try and get them under 100kb each max (some of yours are way over that)
The two main things that will slow any Shopify site down are Apps & Images. So be careful/limited on what client side apps you install and if you uninstall them try and make sure they haven't left any code behind (which is probably what's happened with the 1st issue), for images either optimize them with some software on your computer before uploading them (product images always JPG/JPEG, less than 100kb, usually square approx 1000x1000 px and all the same dimensions (you have images that are different dimensions and it is throwing some of your site layout out) or use one of the automated image apps from the Shopify app store (CrushPics or Bulk Image Edit are the two most popular ones)
Hope that helps.
Site doesn't load very quickly in Chrome either I'm afraid (visually it does but the actual load time is slow due to the 1st issue). For Safari it is most likely to do with images. Chrome supports a format called WebP which automatically takes your images (in JPG or whatever) and serves them as WebP which makes them smaller (Kb) hence they load quicker. Safari does not support WebP so it will just render your default images in whatever size they are served by Shopify.