Hi…I am teaching myself to knit and have been practicing with 15-20 stitches. But…I can not figure out 2 things. 1) when you cast on, there is a little tale left over…what do I do with this? 2) I see scarves and other small pattern that call for 30-50 stithes to cast-on (this I can do)…but I can’t for the life of me figure out how I am going to cast on the 252 that one pattern calls for for an afghan. Do I get really long needles, or is there some trick to this???
Thanks
I am gonna try this one…Umm if you “plan” to work with “straight” needles, I am thinking 14" is the “longest” …and “yes” IMO "cramming 252 sts would be difficult/yet possible. on the other hand “size” of the needle would also play into the equation…think about it, a US size let’s say 6 or7 would probably fit 252…but US 10 or 11 or larger would be a challenge. So, this is when a “circular” needle with
“cables” would be to your advantage…Next “cast on”…you have to do some calculation when doing a long tail cast on. I suggest viewing Amy’s videos on “cast on” to get the idea of your allowance on the “tail”…
I wouldn’t recommend trying to do an afghan on straight needles, you may be able to cram all the stitches on the needle, but I don’t think it would be a comfortable way to work. You really want a circular as cheley mentioned. You can get a lot of stitches on a circular needle. Even if the afghan was supposed to turn out 50 something inches a 36" long needle would probably hold them all.
When you’re finished, or even a few inches along in your project you can weave the leftover ‘tail’ of yarn into the work on the wrong side. And yes, knitting back and forth on a circular needle is the way to handle large numbers of cast on sts.
OMG…my arms and shoulders hurt even thinking about trying to knit an afghan on straight needles. 
Either do it in strips and sew them together or get a long 40" or more circular needle if you’re using worsted weight yarn.
As for your question on a tail… all knitting starts with a tail… you usually want about a 6 inch tail… when your project is complete you will have another tail on the finished edge… You will put the tail on a needle and weave into your knitted work (trying not to let the weaved in areas show). Reason for this is if you just cut that tail short, what can happen is that is can unravel in time or with washings.
As for your second question… Not seeing the pattern, I’m assuming if you are casting on that many stitches, they must be recommending casting onto circular needles… You can’t put that many stitches on straight needles… Hope this helps
, Ok, here’s a quote from my favorite knitter, Lily Chin her book Knitting Tips &Tricks: " The general rule is to reel off three times the width of your piece and add 10 percent of the original width. For instance,for an 8 inch wide scarf, you will need at 24 inches of yarn for the tail plus another .8 for a total of 24.8 inches"
Thank you everyone…I definitely see the need for circular needles for an afghan, and I also see the need to start smaller (say, with a scarf) 