Most important thing to pick up on really is one of the most basic and fundamental Go principles - keep yourself connected, keep your opponent's groups separated (when his groups are independently weak) - and remember the value of sente. If he's threatening to catch an unimportant stone on the edge, it's probably not big enough to care about.
(;GM[1]FF[4]CA[UTF-8]AP[CGoban:3]ST[2]
RU[Japanese]SZ[19]KM[0.50]TM[600]
PW[White]PB[Thimblefox]WR[17k]BR[17k]DT[2015-03-27]RE[B+Resign]LT[]NB[12]NW[12]RR[Normal]
;B[pd]BL[590]
;W[pp]WL[595]
;B[dc]BL[582]
;W[ep]WL[592]
;B[ce]BL[578]
;W[cp]WL[589]
;B[jd]BL[572]
;W[jo]WL[587]
;B[qn]BL[567]
;W[pj]WL[582]C[So this is another thing I have to learn to deal with fuseki wise.
T: it's fine, and yeah, you do

]
;B[qq]BL[498]C[According to Eidogo this joseki is played by white when he plays sanrensei.
T: Invading is fine, good option.]
;W[qo]WL[567]
;B[pq]BL[476]C[T: Good]
;W[oq]WL[561]
(;B[oo]BL[437]LB[op:A]C[Now I find A better.
T: 100% yes, much, much better. Cut / disconnect your opponent, keep your important stuff connected and alive. Rule of thumb for the whole game, every game.]
;W[pr]WL[546]
(;B[ro]BL[414]LB[op:A]C[A still seems like a good option to me.
T: Yes, still vital.]
;W[qp]WL[530]
;B[op]BL[396]
;W[rq]WL[465]
(;B[rp]BL[340]LB[or:A]C[I can cause more trouble with A, I think.
T: I agree, but only if White can't play O3, which requires a fair bit of reading, else O3 is better.]
;W[qr]WL[460]
(;B[po]BL[325]TR[pn][rn]C[T: Most importantly, get into the habit of not leaving these cuts. Q6 is fine.]
;W[np]WL[454]
;B[no]BL[316]
;W[lp]WL[437]
(;B[qk]BL[280]TR[qn]C[I need to connect.
T: R8 and P7 are both better than this]
;W[qm]WL[412]
;B[rm]BL[248]
(;W[pm]WL[400]C[T: Strange!]
;B[pn]BL[239]
;W[om]WL[395]
;B[qj]BL[196]C[T: Good. Settle this big group]
;W[ok]WL[381]
;B[pi]BL[179]
;W[oi]WL[378]
;B[ph]BL[176]C[T: Good, vital move.]
;W[ql]WL[351]
;B[rl]BL[162]
;W[pk]WL[345]
;B[dj]BL[156]LB[co:A]C[I could also approach here. I guess I played this point because I didn't know how to approach this enclosure.
T: It's fine here

]
;W[dk]WL[335]
(;B[cj]BL[148]C[This seemed more reasonable than extending towards the middle.
T: Hane is a good habit.]
;W[ck]WL[324]
;B[ek]BL[144]
;W[ej]WL[321]C[I finally understood that when white cuts here, it can actually work to my advantage, because I can build territory/a wall. ]
(;B[ei]BL[134]C[T: As a rule, atari on a cutting stone here is often bad. Why make White stronger?]
;W[fj]WL[316]
;B[fi]BL[102]
;W[fk]WL[301]
;B[el]BL[83]
;W[fl]WL[297]C[T: A good result for White.]
(;B[dl]BL[70]LB[gi:B][em:A]C[A would've given me more liberties. But then again I guess I simply shouldn't have played there and play at B, or something.
T: The problem was E11, not the following moves.]
;W[cl]WL[293]
(;B[gd]BL[38]
;W[em]WL[288]
;B[dm]BL[26]C[This is just wasting my time and points.
T: Yes, extend at G11.]
;W[dn]WL[286]
;B[fm]BL[589]
;W[en]WL[273]
;B[mo]BL[580]LB[md:A]C[Also not doing that much right now. Maybe I should've just played at A. ]
;W[mp]WL[270]
;B[gi]BL[571]
;W[gm]WL[267]
;B[iq]BL[531]C[Except for poor timing, is there a better move for invading white here? This is one of the things that's bound to be useful to know how to do.]
;W[hq]WL[262]
;B[hp]BL[523]
;W[ip]WL[257]
;B[gq]BL[515]
;W[hr]WL[254]
;B[md]BL[483]C[I guess I gave up on that project.]
;W[gp]WL[246]
;B[dh]BL[472]
;W[bj]WL[236]
;B[ch]BL[443]LB[bi:A]C[Simply playing at A didn't seem safe at the time. But it seems fine now.]
;W[ci]WL[232]
;B[di]BL[439]
;W[bi]WL[228]
;B[bh]BL[432]
;W[gj]WL[218]
;B[hj]BL[421]
;W[hk]WL[206]
;B[ij]BL[406]
;W[ik]WL[202]
;B[ln]BL[358]TR[hj][ij][ln]C[I think I was planning to connect these two groups. Not sure how that would happen though. It doesn't seem very thought through.]
;W[jj]WL[198]
;B[ji]BL[355]
;W[ii]WL[190]
;B[hi]BL[349]
;W[ih]WL[188]
;B[kj]BL[342]
;W[jk]WL[186]
;B[ki]BL[339]
;W[jg]WL[180]
;B[jh]BL[329]
;W[hg]WL[176]
;B[hh]BL[323]C[I didn't want to give him the chance to make eyes too easily.]
;W[ig]WL[173]
;B[kg]BL[307]
;W[gg]WL[154]
;B[ko]BL[271]
;W[kp]WL[151]
;B[ho]BL[260]
;W[hn]WL[144]
;B[io]BL[252]LB[ko:A]C[Maybe A confused him, but my group would have had more chances if I hadn't played it.]
;W[in]WL[139]
;B[jp]BL[240]
;W[jn]WL[136]
;B[go]BL[595]
;W[fp]WL[130]
;B[gr]BL[574]
;W[ir]WL[118]
;B[jr]BL[566]
;W[lo]WL[101]
;B[kn]BL[554]
;W[kq]WL[95]C[Now I also see that I should just ignore this. I can kill the white group before he kills mine, and then I can expand on both sides.]
;B[jq]BL[527]
;W[js]WL[58]
;B[hs]BL[497]
;W[kr]WL[46]
;B[is]BL[492]C[Now I only have the left side.]
;W[ks]WL[41]
;B[fn]BL[487]C[On the one hand, the corner is a lot of points, but on the other I keep his two groups separated.]
;W[fo]WL[35]
;B[gn]BL[482]
;W[fq]WL[31]
;B[fr]BL[479]
;W[er]WL[27]
;B[es]BL[473]
;W[ds]WL[25]
;B[gl]BL[413]
;W[cm]WL[17]
;B[hm]BL[407]
;W[jm]WL[599]
;B[km]BL[367]
;W[kl]WL[592]
;B[mm]BL[323]
;W[ml]WL[578]
;B[ll]BL[305]
;W[lk]WL[574]
;B[lm]BL[294]
;W[lj]WL[563]
;B[kk]BL[280]
;W[jl]WL[556]
;B[gk]BL[260]C[Woho!]
;W[nm]WL[546]
;B[mn]BL[253]
;W[nn]WL[533]
;B[mk]BL[222]
;W[nl]WL[514]
(;B[mj]BL[213]LB[mi:A]C[Playing at A looks more dangerous for white.]
;W[li]WL[510]
;B[kh]BL[210]
;W[mi]WL[506]
;B[nh]BL[200]
;W[on]WL[497]
;B[rn]BL[189]
;W[kf]WL[482]
;B[lg]BL[569]
;W[lf]WL[477]
;B[mg]BL[562]
;W[mf]WL[473]
;B[nf]BL[541]C[This didn't seem very threatening to me at the moment, since he didn't have any eyes. ]
;W[og]WL[464]
;B[oh]BL[518]
;W[ni]WL[451]
;B[ng]BL[455]
;W[pg]WL[440]
;B[qf]BL[449]C[Now I wanted to safeguard my corner. Simply playing R17 seemed way too passive.]
;W[qg]WL[438]
;B[qh]BL[437]
;W[rf]WL[433]
;B[rd]BL[383]
;W[rh]WL[424]
;B[ri]BL[374]
;W[si]WL[420]
;B[sj]BL[360]
;W[sh]WL[417]
;B[qe]BL[314]
;W[re]WL[415]
;B[se]BL[304]
;W[sf]WL[403]
;B[sd]BL[299]
;W[rg]WL[597]
;B[je]BL[265]
;W[jf]WL[585]
;B[ff]BL[254]
;W[fg]WL[582]
;B[ef]BL[245]
;W[eg]WL[579]
;B[dg]BL[231]
;W[df]WL[576]
;B[cf]BL[223]
;W[de]WL[573]
;B[dd]BL[212]
;W[ee]WL[571]
;B[fe]BL[209]
;W[hl]WL[556]
;B[gm]BL[201]
;W[pf]WL[546]
;B[oe]BL[190]C[All I knew was that it was a cutting point, and that now it wasn't anymore. x)]
;W[ne]WL[530]
;B[nd]BL[180]
;W[me]WL[524]
;B[fs]BL[155]
;W[lh]WL[518]
;B[nj]BL[114]
;W[oj]WL[504]
;B[dr]BL[586]
;W[eq]WL[494]
;B[cs]BL[583]
;W[cr]WL[490]
;B[ds]BL[577]LB[br:A]C[A looks better.]
;W[dq]WL[485]
;B[br]BL[574]
;W[bq]WL[482]
;B[bs]BL[563]
;W[qc]WL[478]
;B[qd]BL[555]
;W[pc]WL[476]LB[oc:A]C[White doesn't seem to have that many other options available to him. The peep at A seemed the most promising, but then I could just play at Q17.]
;B[oc]BL[551]
;W[ob]WL[473]
;B[nb]BL[540]
;W[rc]WL[466]
;B[pb]BL[535]
;W[qb]WL[458]
;B[oa]BL[531]
;W[qa]WL[454]
;B[sc]BL[518]
;W[sb]WL[451]
;B[ra]BL[513]
;W[pe]WL[447]
;B[od]BL[508]
;W[ld]WL[587]
;B[lc]BL[503]
;W[mh]WL[566]
;B[kd]BL[466]
;W[of]WL[558]
;B[sg]BL[454]
;OS[])
(;B[mi]))
(;B[gi]C[T: Key point!]))
(;B[em]))
(;B[el]
(;W[ei]
;B[bk]C[T: White has a lot of difficulties now.])
(;W[bj]
;B[bi]
;W[bk]
;B[ch]
;W[cm]
;B[gk])))
(;B[ck]
;W[dl]
;B[cl]C[T: Make points!]))
(;W[pn]
;B[rn]
;W[pm]
;B[pk]
;W[nm]
;B[oj]))
(;B[pm]C[T: This would be my choice, and is simple, but R8 also good.]))
(;B[pn]C[T: Now you cannot be cut, this is a very important habit to get into]))
(;B[or]
;W[nq]
;B[qr]
;W[rr]
;B[ps]
;W[rp]
;B[rn]
;W[rs]
;B[qs]
;W[pn]
;B[po]
;W[pm]
;B[nr]
;W[mq]
;B[mr]
;W[qm]
;B[rm]
;W[rl]
;B[lq]
;W[no]TR[qp]C[T: Now the marked group is alive, This is good for White. Turns out you couldn't play P2.])
(;B[nq]
;W[or]
;B[mp]C[T: Now your shape is robust. Q6 is another possibility]
;W[pn]C[T: White cannot cut this way]
;B[po]
;W[qr]
;B[pm]C[T: As long as this ladder is good for Black, this result is a failure for White]))
(;B[op]))
(;B[op]))