Re: Manual Bidding
You have to determine the Daily Budget first then set the keyword biding accordingly.Your daily budget should be based on your campaign goal/objective and the competition of your targeted keywords,etc.
To analyse the competition for your targeted keywords you can use Keyword Planner.
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Hi Bridge T, I'd actually totally disagree with Shuva here, you should not set your budget then set your Keyword bids, that's entirely the wrong way around. If you have chosen an appropriate set of Keywords for your objective, you should set your budget such that these Keywords have sufficient to receive close to a 100% impression share and a good (in the top 3) Average position.
In short, your budget should be decided by your Keyword bids, not the other way around.
Why? Because you can only truly judge the effectiveness of a Keyword when it is allowed to match against most of the possible search terms. For a Keyword to match most of its search terms it needs to have sufficient budget for it's expected CTR and CPC. So, for example, if a Keyword has an average CPC of $1, a CTR of 5% and can receive 1000 impressions per day, it will require a budget - for that one Keyword alone - of $50 per day.
A very common mistake is to have too many Keywords with too small a budget; this will cause your Keywords - perhaps many or most of them - to be limited in how often they can match a search term so you will not be seeing the true potential of your advertising.
Remember, for an ecommerce site tracking sales, if your Account returns a positive Return on Investment you should continue to increase the budget until no more can be spent. If your Account doesn't return a positive ROI you shouldn't be spending anything. There really is no middle ground.