For making more bitcoins, I guess you need not looking for shorting altcoins. Making use of altcoin trading and just holding bitcoins will help you to earn better in more effective way within short period of time than you expect.
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I am not looking for a profit from the short. I want to hedge my investments, so that I have a net neutral position in that currency while investing in it. To help illustrate, I'll give you an example.

Let's say that I can earn 3% return on an investment by paying the borrower 100 LTC for a period of time. However, according to my stated investment goals, I do not want to be exposed to the risk of fluctuations of LTC.

So
1) I buy 100 LTC with my BTC
2) I make the investment
3) I short a further 100 LTC

This has the effect of canceling out the gains or losses from changes in the value of LTC relative to BTC, leaving me with only the stated 3% goal (minus the fees and vig of these transactions).

While many investors use shorting as a high-risk/high return method of investing, using shorts in this way is a more traditional method of hedging an investment of activity.