Personally I'm pretty bearish on the whole crypto market right now. Presumably you've seen the famous 'bubble' diagram before? ';)
However, I can't quite figure out why LTC is doing so well just now. I guess it's because basically it's the same as BTC but with low fees and no plans to ever have a fee market because the block size would be expanded as required. This would be attractive for business because they could plan ahead without their business model being invalidated down the line due to high fees. Another explanation is that it's just very popular in China (perhaps even more than BTC)!
You could just try to build up your position incrementally over time which is probably the safest way.