Hi, noz03
As Gavron23 already mentioned, we have some very valuable content that will be very helpful once you achieve the needed status. Reading Moshman's and Mersenneary's book will be also helpful!
As for HU advices ( although it depends on stack sizes, type of opponent, previous history etc) my approach will be the this:
If deep enough for postflop play, say 13 BB eff.+ I will go small ball vs the fishy players as we want to play many pots with them IP. I will min raise a wide range on the BTN(SB), mixing it up with limping some hands if they tend to be stations.They will make many mistakes postflop, so I want to take advantage of it. But still-if you opponents tend to be loose passive, pushing hands like low pockets or low Aces for about 13-15bb is still my preferred option as these hands are most likely to be the best preflop, but their playability is reduced postflop.
As for push/fold game, say (10 eff. BB or less) I will usually push a wider range than nash(even any 2 cards will be usually good unless they start adjusting) and tend to call an all in tighter than nash (as fish is passive in general, so I guess they won't be pushing as loose as a reg will). Also, fish tends to raise/call a lot! So my re-steal range will be tighter.
Vs a reg, I will minraise IP a lot. Also my re-steal range will be much wider as a good player will have a loose range on the BTN and a bigger gap between his raise/calling range, therefore we can re-steal more hands profitably.
To narrow this range, I will suggest re-stealing for <20bb eff. with 22+, Ax+, any broadway, mid-high suited connectors, some mid-suited kings etc. Loosen up or tighten up depending on his tendencies.
When in push/fold mode, try to play close to unexploitable strategy such as nash. This way you know the solid reg is is not gaining edge on you.
Also, you should definitely take advantage of our hand evaluation forums imo! This has helped me and many other players big! Our hand judges will be more than happy to help you out. I will post a link to the <5$ SnG Evaluation Forum:
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