Try to avoid try-catch blocks which perform poorly, Exceptions should be used only in unavoidable exceptional situations.
Try to keep JavaScript and CSS in external files and use ‘link’ tags rather than ‘@import’.
Unless it’s necessary should avoid to using ‘Redirect’, Consider ‘Server.Transfer’, it performs better in some conditions.
Should minimize utility of ‘I frames’ in the web pages.
Then images….., correct formatted Images should be used on the basis of its needs, for example: As background image, big image or a screenshot, the effective format is JPG/JPEG. For graphics like button images, header images, footer images, navigation bar images the best format is PNG.
Should try to avoid DOM objects on the web pages, which is heavy weight, it will reduce the performance of web applications.