What follows here is a crash course on how to trade options.  This is how all my cycle trips are getting paid for going forward, so it makes sense to include this.  Hopefully someone can learn something from this and finance their own trips in the same way.

There are two basic types of options:  calls and puts.  A call gives the buyer the right to buy a stock at a price lower than the market price.  A put gives them the option to sell stock at a price higher than at market.  They are effectively designed as insurance so that the option buyer is protected from volatility and uncertain future events.  Of course for this to happen, the buyer pays a premium.

My focus is mainly on the sell side of options.  For this you are selling calls and puts to a buyer.  You are acting as a type of 'insurance salesman' to sell them on the idea that they can be protected from sudden changes in the market.  In exchange, you receive the premium they pay you. 

Eventually the option will expire.  When that happens, it will either be 'in the money'  or 'out of the money'.  Generally speaking, anything expiring in the money carries value to the buyer.  He or she can exercise the option and make a profit.  For example if a stock is trading at $150 around expiration and the option is for a $140 price, the buyer makes a profit if he exercises the option and buys more stock at a discount.  A put option for $160 would also be in the money since he can sell higher than market.   Conversely, anything opposite of this is out of the money, an option expiring like this is worthless.

The ultimate goal of the option seller is to have the option expire worthless and collect the full premium.  You would be surprised to know this happens 80% of the time, so is a strategy worth taking the risk for.  But you don't have to wait until expiry, you can always buy back the option later on for a very low price and make a profit this way -- provided the market is in your favor.   

From a seller's point of view there is a bullish play and a bearish play.  It is the opposite of what a buyer would do, so you need to think like the buyer to make this successful.  That is, if you see a stock as bullish, you can sell put options to the buyer.  You could try to "convince" him for example that the stock is very volatile and he should buy protection in case there is a sudden downside risk.  Meanwhile you believe the stock will go up long term despite that.  You're willing to take on his risk essentially.  You sell the put option to him, the stock indeed goes up, then you profit.  He may have lost, but then again he chose to buy insurance for a disaster that didn't happen.

The bearish play is that you sell call options to a buyer who "believes" that the stock will go up and he should buy from you to get a deal later on the stock.  But you think the stock is actually going down, so the trade is made on this basis.  A good example of this is Boeing, in light of all their trouble it is a good candidate for selling call options.

There are however significant risks to the seller.   This is especially true if you don't have the shares or the cash as collateral to back up your trade.  If you're wrong and the market goes against you, then you're on the hook to either sell shares or pay cash to the buyer if the option expires in the money and he exercises his rights.  

The buyer has much less risk to worry about.  If he's wrong he just loses the premium and gets nothing out of it.  Presumably he wasn't so stupid to bet the whole house on one trade or buy options so close to expiration.  That's why all this is really like insurance.  But you would be amazed how many people really are this stupid:  they see a stock soar and they buy call options about a week left to expiration, thinking the stock will go up more.  What really happens is that the volatility drops like a stone after the stock makes a big upward move because it then consolidates the gains and there is more safety and certainty about the future.  This is known as IV crush.  If it happens close to expiration, the option quickly becomes worthless and the buyer loses big time.

You could argue that the seller can capitalize on this kind of stupidity from the buyer but it's also high risk.  As the seller you could be subject to unlimited losses if you mess this up.  Let's say for example that a sudden news event causes the stock to soar on the day of expiration.  Then it's not unheard of for the buyer to make 600% profit in one day, maybe even an hour, while the seller would actually lose 600%.  Yes, that's right, you can lose way more than what you invested.  That's why it can be rather dangerous to wait until expiration and it's a lot better to close positions early at partial profits.  Buyers in turn are willing to gamble the whole house on trades like this and there are stories of them making 5x returns in a few minutes.  But it's ultimately a stupid strategy for them.

If you know what you're doing as a seller and you manage the risk well, this isn't something to lose sleep over.

Based on all my research, I decided to focus most of my strategy on short puts.  All told, I pulled the trigger on this strategy and got a massive amount of premium immediately in my bank account.  This was with many trades spread out over many stocks.  It will cover my entire cycling trip, provided of course that my bets pay off and the stocks move in the direction as predicted.  If not, then I'm obviously going to lose some of this premium that I collected upfront.  I fully expect that not all these trades will go in my favor.  That's all part of the deal.

One more thing to say about all this:  short selling options ties up margin in your brokerage account.  The reality is that you have to have a lot of capital (cash or shares) to begin with, otherwise this strategy won't work for you and the broker won't allow it.  That is the main reason why beginners stick with the buy side of options.  The fact that most people buy options is one of the key drivers of why selling options is 80% profitable.  This strategy will continue to have an edge as long as most people are risk averse, which generally holds true.