Keep your searches top secret
Your computer stores your searches based on the cookies in your browser. So if you keep searching for a particular route repeatedly you will notice that the flight prices constantly increases. So to avoid this from happening.
Make sure you search for flights in INCOGNITO or PRIVATE BROWSING MODE.
In Google Chrome or Safari, incognito is enabled by hitting Command (or “Control” if using PC), Shift, “N”. For Mozilla Firefox or Internet Explorer, hit Command (or “Control” if using a PC), Shift, “P”. This will open a new browser window where your information is not tracked, thus not inflating prices as you search. Note: if you’re using an older version of OS X, open Safari then click “Safari” in the menu bar, and select “Private Browsing”.
Your cookies are reset each time you re-open an incognito window. So if you want to start with a clean slate for each flight search (so your previous searches aren’t “remembered”, potentially inflating costs), close all your incognito windows, open a new one, and then perform your flight search.