I used Cabots deck clean to clean the deck. Followed by 2 coats of Intergrain ultradeck timber oil (spotted gum) applied 3 hours apart.

Thanks Mitchell,Is it possible to do sanding by hand using tools like uni-pro-hand-sander or would I need to use a belt sander or other automatic tool ...

Thanks a lot for the replies. Appreciate it.Could you also provide some suggestion for the filler/putty product that I can use for filling the cracks ...