I am not an expert at all. So take whatever I write with a Kilo of salt. I am an investor.
When you say Market is at a Peak - This is true, but then you should be aware at what level are you planning to enter. If you decide I will invest in HDFC at 1300 then it is fine. But if you just think market is at a peak and not have a relative second strategy as to at what point you are willing to invest, then you will be waiting on the side lines. (example nifty is at 15800, you should have a strategy that you will enter the market at 15,000 or 15,500 or whatever you are comfortable. However if your intention is to enter at 14,000 then it woul de a long long wait - but no one can predict)
Not sure if you are willing to invest directly in stocks or wish to go by the Mutual Fund level.
Look at the top notch stocks and see where they stand. Maybe the Nifty is at its peak of 15810 but there could be good company such as HDFC (housing company) - it is at CMV 2481 whilst its 52 week high was 2896. If you like this sector, keep a target level in which you will enter.
Similarly there are other individual stocks which you could find out.
If you are inclined to invest your surplus cash eventually in a Mutual Fund, I think you are wasting time by waiting, do start with a small investment instead of waiting.
I fully agree with @Laxman_lucky ETF is a good option, have no clue about Gold though. If you have decided to go through this route, just invest in ETF though sip way or invest daily. I consider ETF has full fledged investment product and not a stop gap product to hold surplus cash.
Also do understand the tax implication in any of the product you decide to chose if your intention is to park your surplus cash.
Disclaimer - I am invested in HDFC and ETF. Again, do not take any advise on face value, do your own research.