So, basically, the best way to start is this;
Dot creation:
Choose height/weight that works best with your dot type and future skill goals.
Know NOW, before you even start, what skills you want to end up high and what skill you will be choosing as your "Primary". (Example... for a Run Blocking Guard that would be Strength)
You must apply the original 25 SP's when you create so max out as much as you can on the 'Primary' skill... then distribute the remaining SP's into other important skills.
The next step gives you 15 SP's to apply. DO NOT APPLY THEM. Instead, hold them for now. They will be used soon enough.
You now have a dot ready to train. If you look you will notice you have 12 BT's and a lot of Training Points (TP's). First, before you do anything, use 6 BT's to enhance your main skill ONE TIME.
Now, LIGHT TRAIN one time ONLY. Now you have 12 BT's again. Enhance your training on your main (Primary) skill a 2nd time.
From here it is up to you. You could simply intense train your Primary until it reaches 34... then use those saved 15 BT's to enhance your primary to the 1st cap...
OR... you could simply train your Primary up to 34 then stop and hold and start on your #2 skill and wait until day -1 (or day -0- if you wanna be risky), then apply the 15 saved SP's to primary...
OR... you could just medium train your primary until you get 18 BT's, enhance training on it a 3rd time, then continue training it even more. Just don't go past 48 of you'll train through a cap (a no-no)...
OR... (are you getting the picture?)
There are many ways to start a dot. And it's likely many people will post their ways after this post. Some will even claim it's "the best". I have tried most all the different ways and can say they'll get you to the end pretty much the same... depending on if you have a PLAN for your dot.
I tend to do a LOT of light training early for BT's to enhance training for all my skills I plan on training in Multi-training as well as the BT's needed to buy slots for those skills. My goal is to be multi-training by day 1 if at all possible... with my Primary skill at 1st cap at least. I know others do it differently than I do so ask around. Pick one and stick with it. Jumping around will only hurt the build.
Find an ALG chart as well. Your "Gold Star" skills are Primaries. Your "Blue Star" skills are secondaries. Primaries get more ALG help when leveling up than Secondary skills do. ALG's are your friend. Never train through a cap. Cap before you boost if at all possible. Cap before a level up if at all possible. (BTW, find a Cap chart too. Very handy!)
Your very best bet is to find a mentor/team that will help you get started right. Also they'll answer questions you have along the way. It's how I did it and it's likely how many others did as well.