This probably happens when you click and drag on a tab while you're selecting it. If that's the case, train your hand to move to the desired tab, stop, click, release then move on.

Another option is to use the keyboard to select tabs. (I'm a Firefox user, and I only ever click the tabs when I want to drag them to reorder them.) Assuming their key bindings are the same as Mozilla's, Ctrl+T opens a new tab, Ctrl+W closes it, Ctrl+Tab moves to the next tab, Ctrl+Shift+Tab moves to the previous tab. To move forward 5 tabs, just hold Ctrl and tap Tab 5 times. It becomes second-nature with just a little practice.