Learn about the market and invest in projects you believe in. You can diversify your portfolio and keep a majority of your investment in a well known currency (for example ETH or BTC).
Before you start trading you need to learn as much as you can about the market. Invest in projects you believe in and always invest an amount that you can afford to lose.
You need to invest in a mining rig (computer machine with several graphic cards). Graphic cards are expensive nowadays and if you can find a good deal then you have a chance to start with a lower investment. Check ether calculator and based on your electricy expenses you can calculate expenses and potential profit.
There are quite a few of website out there. It really depends on your preference. Coincodex.com has a great user interface where you can track prices and news about the crypto world.
Kraken supports only a limited number of coins. If you want to purchase other icos that are not supported you will have to transfer the funds to another exchange.
Once you have purchased coins on the kraken account I suggest you move the coins to a wallet (for better security).
There have been scams in the past and it is harder to distinguish scams nowadays. Before you invest in Ico you need to research on the company, read the whitepaper and make sure their business is legit.