Personally i would get a 2 x 10 Gallon tanks for breeding, one for he fry, one for the Adults.
Both guppies look like they have recently dropped, i would not expect another drop formt hem for around 3-4 weeks, when they do drop again, write down the date, keeping track of dates is a good start because you will start to see a regular dropping pattern.
What is your main purpose for breeding?
Okay I will definitely look into getting more then one tank then, I was kind of questioning that. My main purpose for breeding them.. Well I actually didn't have a purpose I was looking for a new fish to start with because I used to work with Betta's a lot when I was younger and always had full batches of fry that died so I didn't really want to try them again, but I had gotten rid of most of my tanks so I was just assuming I could get a few guppies and then get some large tanks and just keep a steady amount in there. I had read up on them a lot but I didn't plan on buying pregnant females, in fact I had my male and females in separate tanks just to avoid this very thing. But I have got a Notebook on hand so I can get the date and everything Jotted down, I am defiantly trying to get as much out of this experience as possible. I'll be getting one 10gallon tank around January 30-February 2 so I'm hoping they'll hold off until then

:3
What i would do if i was you is buy some really young females, obviously will not know straight away if they have bred but leave them 7 months and this way they will free of any sperm packets if they have been caught pregnant, then you can start to choose your strain carefully and pick a really nice male and experminet on trying to keep a nice strain.
Anyways back to your main concern, You could actually have have 4 adult fish in say a 7-8 gallon tank (guppies). Then get a 10G tank for the fry, now what i did when i was breeding livebearers is i bought a couple of breeding traps and placed them in the 10G tank, when the females was ready to drop i placed hem in the trap and when they was done i put them back in thier tank and depending on if i already had fry in the 10G already and depending on thier size, i would release the fry ou of the traps either straight away or wait a week. I had the 10G tank very heavily planted.
Now another way is to just put the female straight in the 10G tank if its heavily planted and let her drop fry in it, but over the years i have seen the mother eat so many fry this way, traps was the best way to go for me.
As long as u don abuse the traps, they are really good, never leave the female in longer than 48 hours (but the more experience u have and goping by dates etc, u will find this wont happen) and turn the lights out when u put female in trap to minimize the stress and also add a little bit of food.
Diet is important when breeding too, and keeping up with regular water changes, the better your water quality and thier diet, the more sucess you will have.
Keep away from any sort of deformities in the fish, never let one enter your breeding colony its very important, also any deformities your fish have, i know its harsh but you must get rid of them.
Temperature matters to, depending on your temps, you will get more males at lower temps (23-25), and more females at higher temps(26-29).
I always keep my tanks at 26 degrees, and tend to get a mixutre of both most of the time.
If you have any questions about anything, anything at all, please ask, im happy to help.