A few weeks ago I described how I run the "Krypto Fund", which is the name for my long-term investment portfolio where I keep the bulk of my investments. The Krypto Fund is completely indexed across several asset classes and is aggressively rebalanced. The amount I keep in it as a percentage of net investable assets varies with my inclination to work & opportunities. In my current state of semi-retirement, I keep 70-80% of net investable assets there. [Fwiw, when I was aggressively trading short-term, I kept less in the Krypto Fund as I was able to get 50-100% returns by working very, very hard at trading very aggressively with mucho margin and options.]
What about the other 20-30%? That includes all my "alpha" plays - the "Alpha Fund" - where I invest in stocks & sectors that I think will outperform. My time frame varies and can change, especially with significant news. I try to get long-term capital gains, but will sell if I think the news merits. For example, as I posted in mid-February, I sold many positions to cut back when the CPI news was unfavorable, even though that realized short-term gains. [Better a ST gain than lost profits]
The Alpha Fund is now 24%. I have about 6% in India stocks, about 12% in oil and oil service stocks, about 3.5% in mineral stocks, and assorted others such as AAPL, EDU, ORCL, CRXL etc. The Alpha Fund can use margin, btw. I had it 200% long until mid-February. Now it's about 120% long - my oil plays are using some margin as I keep finding good stocks there and don't want to sell until I can realize long-term gains in midsummer (I loaded up the big dips last summer).
I think by compartmentalizing investments this way one can control risk, yet "stay in the game" through the "Alpha Fund". I can keep position and sector size under control while having a stable core base of investments to let me stay "semi-retired". [btw, my commodity speculation funds are completely separate.]