tough

it is never easy for a beginner. setting a stop loss and profit target is similar to timing the market. you never know what is coming next.
I personally experienced this. i set a stop loss target to prevent myself from losing too much, and sold a portion of my holdings. Next moments, the stock went northward.
i have also sold holdings for profit taking, but only to regret later on if the price continue to rise, and more costly for re-entry.
My thought is that, we can only take the news and the market trends as a form of reference whether the market is volatile and whether we should exit. If not, hold on to the stocks you had chosen if you still have faith in them and feel that their business is still relatable to our day-to-day lives or needs. Buy the dips.
Of cause, if the business belongs to the dying market (ie, company still selling pagers, fax machines etc), please exit.
I am no expert, and not ripping huge profit from the markets. But i am neither making huge losses. Just sharing my thoughts.

Personally, i have not done it. But what i did before was tapping into extra savings, to invest.
I do not object borrowing money to invest. But do it in a safe manner and know what you are buying into. You need money to roll money, and if the price is right and opportunity presented itself, it will be a missed opportunity if we do not have the capital to invest. 1% returns of $100k is a profit $1000, compared to a 50% return of $1000, you only profitted $500.
If we have the larger capital to invest and leverage on small percentage profit margin, we will still earning a much more decent return than having small capital for investment. Also, it is much more easier to find a stock to give you a 1% returns than finding a super stock that give 50% profit. And the duration to hit the 1% returns will definitely be a shorter wait. you will not have to hold on to your stock for long time.
Thus, i feel that it is definitely alright to borrow to invest. But make sure you know what you are investing on....